Whittenburg Mark G

SEC source: 0001856525-26-000025 · wk-form4_1773444255.xml · nonDerivative · entry 1

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 8,525

F1 · shares: Represents shares withheld by the Issuer for tax withholding purposes upon the vesting of a portion of restricted stock units granted to the reporting person.

SEC source: 0001856525-26-000010 · wk-form4_1773263471.xml · nonDerivative · entry 2

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 8,856

F1 · shares: Represents shares withheld by the Issuer for tax withholding purposes upon the vesting of a portion of restricted stock units granted to the reporting person.

SEC source: 0001856525-26-000010 · wk-form4_1773263471.xml · nonDerivative · entry 1

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,413

F1 · shares: Represents shares withheld by the Issuer for tax withholding purposes upon the vesting of a portion of restricted stock units granted to the reporting person.

SEC source: 0001866737-26-000002 · wk-form4_1767395596.xml · derivative · entry 1

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Indirect · By LLC

Disclosed balance after: 227,312

Underlying: Class A Common Stock · 25,500 shares

Expires not disclosed

F1 · derivative.exercise_price: Pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") are exchangeable at the discretion of the reporting person for shares of Class A common stock of the Issuer ("Class A common stock") on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F2 · derivative.exercise_price: Represents securities held by Core & Main Management Feeder, LLC ("Management Feeder") in respect of 25,500 vested common units (the "Charitable Donation Units") transferred by the reporting person to a donor-advised fund on December 31, 2025 (the "Charitable Donation Effective Date"). Pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Management Feeder, dated as of February 13, 2024 (as amended, the "LLC Agreement"), such Charitable Donation Units held by the donor-advised fund are redeemable at the discretion of the donor-advised fund for Paired Interests, on a one-for-one basis.

F1 · date: Pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") are exchangeable at the discretion of the reporting person for shares of Class A common stock of the Issuer ("Class A common stock") on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F2 · date: Represents securities held by Core & Main Management Feeder, LLC ("Management Feeder") in respect of 25,500 vested common units (the "Charitable Donation Units") transferred by the reporting person to a donor-advised fund on December 31, 2025 (the "Charitable Donation Effective Date"). Pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Management Feeder, dated as of February 13, 2024 (as amended, the "LLC Agreement"), such Charitable Donation Units held by the donor-advised fund are redeemable at the discretion of the donor-advised fund for Paired Interests, on a one-for-one basis.

F3 · kind: Represents a gift/charitable donation of the 25,500 Charitable Donation Units held directly by the reporting person to the National Philanthropic Trust, a Pennsylvania non-profit corporation, to be held in a donor-advised fund.

F1 · derivative.exercise_date: Pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") are exchangeable at the discretion of the reporting person for shares of Class A common stock of the Issuer ("Class A common stock") on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F2 · derivative.exercise_date: Represents securities held by Core & Main Management Feeder, LLC ("Management Feeder") in respect of 25,500 vested common units (the "Charitable Donation Units") transferred by the reporting person to a donor-advised fund on December 31, 2025 (the "Charitable Donation Effective Date"). Pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Management Feeder, dated as of February 13, 2024 (as amended, the "LLC Agreement"), such Charitable Donation Units held by the donor-advised fund are redeemable at the discretion of the donor-advised fund for Paired Interests, on a one-for-one basis.

F1 · derivative.expiration_date: Pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") are exchangeable at the discretion of the reporting person for shares of Class A common stock of the Issuer ("Class A common stock") on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F2 · derivative.expiration_date: Represents securities held by Core & Main Management Feeder, LLC ("Management Feeder") in respect of 25,500 vested common units (the "Charitable Donation Units") transferred by the reporting person to a donor-advised fund on December 31, 2025 (the "Charitable Donation Effective Date"). Pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Management Feeder, dated as of February 13, 2024 (as amended, the "LLC Agreement"), such Charitable Donation Units held by the donor-advised fund are redeemable at the discretion of the donor-advised fund for Paired Interests, on a one-for-one basis.

F1 · ownership.direct: Pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") are exchangeable at the discretion of the reporting person for shares of Class A common stock of the Issuer ("Class A common stock") on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

SEC source: 0001856525-25-000119 · wk-form4_1749597810.xml · derivative · entry 10

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 49,100 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F8 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F8 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F5 · kind: On June 9, 2025, pursuant to the terms of the Exchange Agreement, 49,100 shares of Class B common stock and a Paired Interest were exchanged for shares of Class A common stock, on a one-for-one basis.

F5 · shares: On June 9, 2025, pursuant to the terms of the Exchange Agreement, 49,100 shares of Class B common stock and a Paired Interest were exchanged for shares of Class A common stock, on a one-for-one basis.

F8 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F8 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

SEC source: 0001856525-25-000119 · wk-form4_1749597810.xml · derivative · entry 9

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 49,100

Underlying: Class A Common Stock · 49,100 shares

Expires not disclosed

F8 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F8 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F6 · shares: On June 9, 2025, pursuant to the terms of the LLC Agreement, 49,100 vested Units held directly by the reporting person were redeemed at the discretion of the reporting person for 49,100 Paired Interests.

F8 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F8 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

SEC source: 0001856525-25-000119 · wk-form4_1749597810.xml · derivative · entry 8

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Indirect · By LLC

Disclosed balance after: 252,812

Underlying: Class A Common Stock · 49,100 shares

Expires not disclosed

F8 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · derivative.exercise_price: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F8 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F6 · shares: On June 9, 2025, pursuant to the terms of the LLC Agreement, 49,100 vested Units held directly by the reporting person were redeemed at the discretion of the reporting person for 49,100 Paired Interests.

F8 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · derivative.exercise_date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F8 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · derivative.expiration_date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F9 · ownership.direct: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

SEC source: 0001856525-25-000119 · wk-form4_1749597810.xml · nonDerivative · entry 4

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 9,691

F3 · kind: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on October 11, 2024.

F7 · price: The price reported represents the weighted average price of shares of Class A common stock sold in multiple transactions at prices ranging from $60.0000 to $60.1000 per share. The reporting person will provide to the Issuer, or the Securities and Exchange Commission staff, upon request, information regarding the number of shares sold at each price within the range.

SEC source: 0001856525-25-000119 · wk-form4_1749597810.xml · nonDerivative · entry 3

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 58,791

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F5 · kind: On June 9, 2025, pursuant to the terms of the Exchange Agreement, 49,100 shares of Class B common stock and a Paired Interest were exchanged for shares of Class A common stock, on a one-for-one basis.

F6 · shares: On June 9, 2025, pursuant to the terms of the LLC Agreement, 49,100 vested Units held directly by the reporting person were redeemed at the discretion of the reporting person for 49,100 Paired Interests.

SEC source: 0001856525-25-000119 · wk-form4_1749597810.xml · derivative · entry 7

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 900 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F8 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F8 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F1 · kind: On June 6, 2025, pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), 900 shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") were exchanged for shares of Class A common stock of the Issuer ("Class A common stock"), on a one-for-one basis.

F1 · shares: On June 6, 2025, pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), 900 shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") were exchanged for shares of Class A common stock of the Issuer ("Class A common stock"), on a one-for-one basis.

F8 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F8 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

SEC source: 0001856525-25-000119 · wk-form4_1749597810.xml · derivative · entry 6

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 900

Underlying: Class A Common Stock · 900 shares

Expires not disclosed

F8 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F8 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F2 · shares: On June 6, 2025, pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Core & Main Management Feeder, LLC ("Management Feeder"), dated as of February 13, 2024 (as amended, the "LLC Agreement"), 900 vested common units ("Units") held directly by the reporting person were redeemed at the discretion of the reporting person for 900 Paired Interests.

F8 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F8 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

SEC source: 0001856525-25-000119 · wk-form4_1749597810.xml · derivative · entry 5

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Indirect · By LLC

Disclosed balance after: 301,912

Underlying: Class A Common Stock · 900 shares

Expires not disclosed

F8 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · derivative.exercise_price: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F8 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F2 · shares: On June 6, 2025, pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Core & Main Management Feeder, LLC ("Management Feeder"), dated as of February 13, 2024 (as amended, the "LLC Agreement"), 900 vested common units ("Units") held directly by the reporting person were redeemed at the discretion of the reporting person for 900 Paired Interests.

F8 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · derivative.exercise_date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F8 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · derivative.expiration_date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F9 · ownership.direct: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

SEC source: 0001856525-25-000119 · wk-form4_1749597810.xml · nonDerivative · entry 2

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 9,691

F3 · kind: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on October 11, 2024.

F4 · price: The price reported represents the weighted average price of shares of Class A common stock sold in multiple transactions at prices ranging from $60.0000 to $60.0550 per share. The reporting person will provide to the Issuer, or the Securities and Exchange Commission staff, upon request, information regarding the number of shares sold at each price within the range.

SEC source: 0001856525-25-000119 · wk-form4_1749597810.xml · nonDerivative · entry 1

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 10,591

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · kind: On June 6, 2025, pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), 900 shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") were exchanged for shares of Class A common stock of the Issuer ("Class A common stock"), on a one-for-one basis.

F2 · shares: On June 6, 2025, pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Core & Main Management Feeder, LLC ("Management Feeder"), dated as of February 13, 2024 (as amended, the "LLC Agreement"), 900 vested common units ("Units") held directly by the reporting person were redeemed at the discretion of the reporting person for 900 Paired Interests.

SEC source: 0001856525-25-000074 · wk-form4_1742259010.xml · derivative · entry 2

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 24,828

Underlying: Class A Common Stock · 24,828 shares

Expires 2035-03-13

F2 · derivative.exercise_date: The options vest in three equal installments on March 11, 2026, March 11, 2027 and March 11, 2028, subject to the terms of the associated Participant Stock Option Agreement.

SEC source: 0001856525-25-000074 · wk-form4_1742259010.xml · nonDerivative · entry 1

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,691

F1 · shares: Represents restricted stock units ("RSUs") granted to the reporting person. Each RSU represents a contingent right to receive one share of Class A common stock of the Issuer. The RSUs vest in three equal annual installments on March 11, 2026, March 11, 2027 and March 11, 2028, subject to the terms of the associated Participant Restricted Stock Unit Agreement.

SEC source: 0001856525-25-000052 · wk-form4_1741900294.xml · nonDerivative · entry 1

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 6,280

F1 · shares: Represents shares withheld by the Issuer for tax withholding purposes upon the vesting of a portion of restricted stock units ("RSUs") granted to the reporting person.

SEC source: 0001856525-25-000040 · wk-form4_1741733594.xml · nonDerivative · entry 2

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 6,790

F1 · shares: Represents shares withheld by the Issuer for tax withholding purposes upon the vesting of a portion of restricted stock units ("RSUs") granted to the reporting person.

SEC source: 0001856525-25-000040 · wk-form4_1741733594.xml · nonDerivative · entry 1

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 7,389

F1 · shares: Represents shares withheld by the Issuer for tax withholding purposes upon the vesting of a portion of restricted stock units ("RSUs") granted to the reporting person.

SEC source: 0001856525-25-000022 · wk-form4_1737151248.xml · derivative · entry 10

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 48,026 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F9 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F6 · shares: On January 16, 2025, pursuant to the terms of the Exchange Agreement, 48,026 shares of Class B common stock and a Paired Interest were exchanged for shares of Class A common stock, on a one-for-one basis.

F9 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

SEC source: 0001856525-25-000022 · wk-form4_1737151248.xml · derivative · entry 9

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 48,026

Underlying: Class A Common Stock · 48,026 shares

Expires not disclosed

F9 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F7 · shares: On January 16, 2025, pursuant to the terms of the LLC Agreement, 48,026 vested Units held directly by the reporting person were redeemed at the discretion of the reporting person for 48,026 Paired Interests.

F9 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

SEC source: 0001856525-25-000022 · wk-form4_1737151248.xml · derivative · entry 8

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Indirect · By LLC

Disclosed balance after: 302,812

Underlying: Class A Common Stock · 48,026 shares

Expires not disclosed

F9 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F10 · derivative.exercise_price: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F9 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F10 · date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F7 · shares: On January 16, 2025, pursuant to the terms of the LLC Agreement, 48,026 vested Units held directly by the reporting person were redeemed at the discretion of the reporting person for 48,026 Paired Interests.

F9 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F10 · derivative.exercise_date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F9 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F10 · derivative.expiration_date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F10 · ownership.direct: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

SEC source: 0001856525-25-000022 · wk-form4_1737151248.xml · nonDerivative · entry 4

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 7,667

F4 · kind: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on October 11, 2024.

F8 · price: The price reported represents the weighted average price of shares of Class A common stock sold in multiple transactions at prices ranging from $55.0000 to $55.2450 per share. The reporting person will provide to the Issuer, or the Securities and Exchange Commission staff, upon request, information regarding the number of shares sold at each price within the range.

F3 · balance_after: Includes 7,667 restricted stock units ("RSUs") granted to the reporting person and remaining unvested, as of the date of this Form 4. Each RSU represents a contingent right to receive one share of Class A common stock. The unvested portion of the RSUs granted on March 11, 2022 vest on March 11, 2025. The RSUs granted on March 10, 2023 vest in two equal installments on March 10, 2025 and March 10, 2026. The RSUs granted on March 7, 2024 vest in three equal installments on March 7, 2025, March 7, 2026 and March 7, 2027. All RSU vesting is subject to the terms of the associated Participant Restricted Stock Unit Agreement.

SEC source: 0001856525-25-000022 · wk-form4_1737151248.xml · nonDerivative · entry 3

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 55,693

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F6 · kind: On January 16, 2025, pursuant to the terms of the Exchange Agreement, 48,026 shares of Class B common stock and a Paired Interest were exchanged for shares of Class A common stock, on a one-for-one basis.

F7 · shares: On January 16, 2025, pursuant to the terms of the LLC Agreement, 48,026 vested Units held directly by the reporting person were redeemed at the discretion of the reporting person for 48,026 Paired Interests.

F3 · balance_after: Includes 7,667 restricted stock units ("RSUs") granted to the reporting person and remaining unvested, as of the date of this Form 4. Each RSU represents a contingent right to receive one share of Class A common stock. The unvested portion of the RSUs granted on March 11, 2022 vest on March 11, 2025. The RSUs granted on March 10, 2023 vest in two equal installments on March 10, 2025 and March 10, 2026. The RSUs granted on March 7, 2024 vest in three equal installments on March 7, 2025, March 7, 2026 and March 7, 2027. All RSU vesting is subject to the terms of the associated Participant Restricted Stock Unit Agreement.

SEC source: 0001856525-25-000022 · wk-form4_1737151248.xml · derivative · entry 7

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 1,974 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F9 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F1 · kind: On January 15, 2025, pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), 1,974 shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") were exchanged for shares of Class A common stock of the Issuer ("Class A common stock"), on a one-for-one basis.

F1 · shares: On January 15, 2025, pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), 1,974 shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") were exchanged for shares of Class A common stock of the Issuer ("Class A common stock"), on a one-for-one basis.

F9 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

SEC source: 0001856525-25-000022 · wk-form4_1737151248.xml · derivative · entry 6

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 1,974

Underlying: Class A Common Stock · 1,974 shares

Expires not disclosed

F9 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F2 · shares: On January 15, 2025, pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Core & Main Management Feeder, LLC ("Management Feeder"), dated as of July 22, 2021 (as amended, the "LLC Agreement"), 1,974 vested common units ("Units") held directly by the reporting person were redeemed at the discretion of the reporting person for 1,974 Paired Interests.

F9 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

SEC source: 0001856525-25-000022 · wk-form4_1737151248.xml · derivative · entry 5

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Indirect · By LLC

Disclosed balance after: 350,838

Underlying: Class A Common Stock · 1,974 shares

Expires not disclosed

F9 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F10 · derivative.exercise_price: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F9 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F10 · date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F2 · shares: On January 15, 2025, pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Core & Main Management Feeder, LLC ("Management Feeder"), dated as of July 22, 2021 (as amended, the "LLC Agreement"), 1,974 vested common units ("Units") held directly by the reporting person were redeemed at the discretion of the reporting person for 1,974 Paired Interests.

F9 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F10 · derivative.exercise_date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F9 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F10 · derivative.expiration_date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F10 · ownership.direct: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

SEC source: 0001856525-25-000022 · wk-form4_1737151248.xml · nonDerivative · entry 2

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 7,667

F4 · kind: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on October 11, 2024.

F5 · price: The price reported represents the weighted average price of shares of Class A common stock sold in multiple transactions at prices ranging from $55.0000 to $55.6800 per share. The reporting person will provide to the Issuer, or the Securities and Exchange Commission staff, upon request, information regarding the number of shares sold at each price within the range.

F3 · balance_after: Includes 7,667 restricted stock units ("RSUs") granted to the reporting person and remaining unvested, as of the date of this Form 4. Each RSU represents a contingent right to receive one share of Class A common stock. The unvested portion of the RSUs granted on March 11, 2022 vest on March 11, 2025. The RSUs granted on March 10, 2023 vest in two equal installments on March 10, 2025 and March 10, 2026. The RSUs granted on March 7, 2024 vest in three equal installments on March 7, 2025, March 7, 2026 and March 7, 2027. All RSU vesting is subject to the terms of the associated Participant Restricted Stock Unit Agreement.

SEC source: 0001856525-25-000022 · wk-form4_1737151248.xml · nonDerivative · entry 1

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 9,641

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · kind: On January 15, 2025, pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), 1,974 shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") were exchanged for shares of Class A common stock of the Issuer ("Class A common stock"), on a one-for-one basis.

F2 · shares: On January 15, 2025, pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Core & Main Management Feeder, LLC ("Management Feeder"), dated as of July 22, 2021 (as amended, the "LLC Agreement"), 1,974 vested common units ("Units") held directly by the reporting person were redeemed at the discretion of the reporting person for 1,974 Paired Interests.

F3 · balance_after: Includes 7,667 restricted stock units ("RSUs") granted to the reporting person and remaining unvested, as of the date of this Form 4. Each RSU represents a contingent right to receive one share of Class A common stock. The unvested portion of the RSUs granted on March 11, 2022 vest on March 11, 2025. The RSUs granted on March 10, 2023 vest in two equal installments on March 10, 2025 and March 10, 2026. The RSUs granted on March 7, 2024 vest in three equal installments on March 7, 2025, March 7, 2026 and March 7, 2027. All RSU vesting is subject to the terms of the associated Participant Restricted Stock Unit Agreement.

SEC source: 0001856525-25-000009 · wk-form4_1736900234.xml · derivative · entry 8

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 46,452 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F7 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F7 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F3 · kind: On January 10, 2025, pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), 46,452 shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") were exchanged for shares of Class A common stock of the Issuer ("Class A common stock"), on a one-for-one basis.

F3 · shares: On January 10, 2025, pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), 46,452 shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") were exchanged for shares of Class A common stock of the Issuer ("Class A common stock"), on a one-for-one basis.

F7 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F7 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

SEC source: 0001856525-25-000009 · wk-form4_1736900234.xml · derivative · entry 7

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 46,452

Underlying: Class A Common Stock · 46,452 shares

Expires not disclosed

F7 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F7 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F4 · shares: On January 10, 2025, pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Core & Main Management Feeder, LLC ("Management Feeder"), dated as of February 13, 2024 (as amended, the "LLC Agreement"), 46,452 vested common units ("Units") held directly by the reporting person were redeemed at the discretion of the reporting person for 46,452 Paired Interests.

F7 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F7 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

SEC source: 0001856525-25-000009 · wk-form4_1736900234.xml · derivative · entry 6

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Indirect · By LLC

Disclosed balance after: 352,812

Underlying: Class A Common Stock · 46,452 shares

Expires not disclosed

F7 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F8 · derivative.exercise_price: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F7 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F8 · date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F4 · shares: On January 10, 2025, pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Core & Main Management Feeder, LLC ("Management Feeder"), dated as of February 13, 2024 (as amended, the "LLC Agreement"), 46,452 vested common units ("Units") held directly by the reporting person were redeemed at the discretion of the reporting person for 46,452 Paired Interests.

F7 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F8 · derivative.exercise_date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F7 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F8 · derivative.expiration_date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F8 · ownership.direct: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

SEC source: 0001856525-25-000009 · wk-form4_1736900234.xml · nonDerivative · entry 5

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 7,667

F5 · kind: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on October 11, 2024.

F6 · price: The price reported represents the weighted average price of shares of Class A common stock sold in multiple transactions at prices ranging from $50.1600 to $51.0175 per share. The reporting person will provide to the Issuer, or the Securities and Exchange Commission staff, upon request, information regarding the number of shares sold at each price within the range.

F2 · balance_after: Of the 12,933 RSUs originally granted an aggregate of 1,718 shares of Class A common stock have been forfeited to the Issuer for tax withholdings purposes and an aggregate of 3,548 shares of Class A common stock have vested and sold with 7,667 RSUs remaining unvested, as of the date of this Form 4. Each RSU represents a contingent right to receive one share of Class A common stock. The unvested portion of the RSUs granted on March 11, 2022 vest on March 11, 2025. The RSUs granted on March 10, 2023 vest in two equal installments on March 10, 2025 and March 10, 2026. The RSUs granted on March 7, 2024 vest in three equal installments on March 7, 2025, March 7, 2026 and March 7, 2027. All RSU vesting is subject to the terms of the associated Participant Restricted Stock Unit Agreement.

SEC source: 0001856525-25-000009 · wk-form4_1736900234.xml · nonDerivative · entry 4

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 57,667

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F3 · kind: On January 10, 2025, pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), 46,452 shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") were exchanged for shares of Class A common stock of the Issuer ("Class A common stock"), on a one-for-one basis.

F4 · shares: On January 10, 2025, pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Core & Main Management Feeder, LLC ("Management Feeder"), dated as of February 13, 2024 (as amended, the "LLC Agreement"), 46,452 vested common units ("Units") held directly by the reporting person were redeemed at the discretion of the reporting person for 46,452 Paired Interests.

F2 · balance_after: Of the 12,933 RSUs originally granted an aggregate of 1,718 shares of Class A common stock have been forfeited to the Issuer for tax withholdings purposes and an aggregate of 3,548 shares of Class A common stock have vested and sold with 7,667 RSUs remaining unvested, as of the date of this Form 4. Each RSU represents a contingent right to receive one share of Class A common stock. The unvested portion of the RSUs granted on March 11, 2022 vest on March 11, 2025. The RSUs granted on March 10, 2023 vest in two equal installments on March 10, 2025 and March 10, 2026. The RSUs granted on March 7, 2024 vest in three equal installments on March 7, 2025, March 7, 2026 and March 7, 2027. All RSU vesting is subject to the terms of the associated Participant Restricted Stock Unit Agreement.

SEC source: 0001856525-24-000046 · wk-form4_1713902686.xml · derivative · entry 5

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 50,000 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F7 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F7 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F1 · kind: On April 19, 2024, pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), 50,000 shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") were exchanged for shares of Class A common stock of the Issuer ("Class A common stock"), on a one-for-one basis.

F1 · shares: On April 19, 2024, pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), 50,000 shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") were exchanged for shares of Class A common stock of the Issuer ("Class A common stock"), on a one-for-one basis.

F7 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F7 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

SEC source: 0001856525-24-000046 · wk-form4_1713902686.xml · derivative · entry 4

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 50,000

Underlying: Class A Common Stock · 50,000 shares

Expires not disclosed

F7 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F7 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F2 · shares: On April 19, 2024, pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Core & Main Management Feeder, LLC ("Management Feeder"), dated as of July 22, 2021 (as amended, the "LLC Agreement"), 50,000 vested common units ("Units") held directly by the reporting person were redeemed at the discretion of the reporting person for 50,000 Paired Interests.

F7 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F7 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

SEC source: 0001856525-24-000046 · wk-form4_1713902686.xml · derivative · entry 3

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Indirect · By LLC

Disclosed balance after: 399,264

Underlying: Class A Common Stock · 50,000 shares

Expires not disclosed

F6 · derivative.exercise_price: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F7 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F6 · date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F7 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F2 · shares: On April 19, 2024, pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Core & Main Management Feeder, LLC ("Management Feeder"), dated as of July 22, 2021 (as amended, the "LLC Agreement"), 50,000 vested common units ("Units") held directly by the reporting person were redeemed at the discretion of the reporting person for 50,000 Paired Interests.

F6 · derivative.exercise_date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F7 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F6 · derivative.expiration_date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F7 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F6 · ownership.direct: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

SEC source: 0001856525-24-000046 · wk-form4_1713902686.xml · nonDerivative · entry 2

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 12,933

F4 · kind: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 19, 2023.

F5 · price: The price reported represents the weighted average price of shares of Class A common stock sold in multiple transactions at prices ranging from $53.5500 to $54.8900 per share. The reporting person will provide to the Issuer, or the Securities and Exchange Commission staff, upon request, information regarding the number of shares sold at each price within the range.

F3 · balance_after: Includes 12,933 restricted stock units ("RSUs") granted to the reporting person. Each RSU represents a contingent right to receive one share of Class A common stock. The unvested portion of the RSUs granted on March 11, 2022 vests on March 11, 2025, subject to the terms of the associated Participant Restricted Stock Unit Agreement. The unvested portion of the RSUs granted on March 10, 2023 vests in two equal installments on March 10, 2025 and March 10, 2026, subject to the terms of the associated Participant Restricted Stock Unit Agreement. The unvested portion of the RSUs granted on March 7, 2024 vests in three equal installments on March 7, 2025, March 7, 2026 and March 7, 2027, subject to the terms of the associated Participant Restricted Stock Unit Agreement.

SEC source: 0001856525-24-000046 · wk-form4_1713902686.xml · nonDerivative · entry 1

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 62,933

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · kind: On April 19, 2024, pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), 50,000 shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") were exchanged for shares of Class A common stock of the Issuer ("Class A common stock"), on a one-for-one basis.

F2 · shares: On April 19, 2024, pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Core & Main Management Feeder, LLC ("Management Feeder"), dated as of July 22, 2021 (as amended, the "LLC Agreement"), 50,000 vested common units ("Units") held directly by the reporting person were redeemed at the discretion of the reporting person for 50,000 Paired Interests.

F3 · balance_after: Includes 12,933 restricted stock units ("RSUs") granted to the reporting person. Each RSU represents a contingent right to receive one share of Class A common stock. The unvested portion of the RSUs granted on March 11, 2022 vests on March 11, 2025, subject to the terms of the associated Participant Restricted Stock Unit Agreement. The unvested portion of the RSUs granted on March 10, 2023 vests in two equal installments on March 10, 2025 and March 10, 2026, subject to the terms of the associated Participant Restricted Stock Unit Agreement. The unvested portion of the RSUs granted on March 7, 2024 vests in three equal installments on March 7, 2025, March 7, 2026 and March 7, 2027, subject to the terms of the associated Participant Restricted Stock Unit Agreement.

SEC source: 0001856525-24-000040 · wk-form4_1711488074.xml · derivative · entry 7

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Class A Common Stock · 49,940 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F9 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F4 · kind: On March 22, 2024, pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), 49,940 shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") were exchanged for shares of Class A common stock, on a one-for-one basis.

F4 · shares: On March 22, 2024, pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), 49,940 shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") were exchanged for shares of Class A common stock, on a one-for-one basis.

F9 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

SEC source: 0001856525-24-000040 · wk-form4_1711488074.xml · derivative · entry 6

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 49,940

Underlying: Class A Common Stock · 49,940 shares

Expires not disclosed

F9 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F5 · shares: On March 22, 2024, pursuant to the terms of the LLC Agreement, 49,940 vested Units held directly by the reporting person were redeemed at the discretion of the reporting person for 49,940 Paired Interests.

F9 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F9 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

SEC source: 0001856525-24-000040 · wk-form4_1711488074.xml · derivative · entry 5

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Indirect · By LLC

Disclosed balance after: 449,264

Underlying: Class A Common Stock · 49,940 shares

Expires not disclosed

F8 · derivative.exercise_price: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F9 · derivative.exercise_price: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F8 · date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F9 · date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F5 · shares: On March 22, 2024, pursuant to the terms of the LLC Agreement, 49,940 vested Units held directly by the reporting person were redeemed at the discretion of the reporting person for 49,940 Paired Interests.

F8 · derivative.exercise_date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F9 · derivative.exercise_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F8 · derivative.expiration_date: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

F9 · derivative.expiration_date: Pursuant to the terms of the Exchange Agreement, Paired Interests are exchangeable at the discretion of the reporting person for shares of Class A common stock on a one-for-one basis or, at the election of a majority of the disinterested members of the Issuer's board of directors, for cash from a substantially concurrent public offering or private sale (based on the price of Class A common stock sold in such public offering or private sale, net of any underwriting discounts and commissions, for each limited partnership interest exchanged, subject to certain exceptions, conditions and adjustments). The Class B common stock and limited partnership interests have no expiration date.

F8 · ownership.direct: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for Paired Interests, on a one-for-one basis.

SEC source: 0001856525-24-000040 · wk-form4_1711488074.xml · nonDerivative · entry 4

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,933

F6 · kind: The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 19, 2023.

F7 · price: The price reported represents the weighted average price of shares of Class A common stock sold in multiple transactions at prices ranging from $57.3000 to $58.2400 per share. The reporting person will provide to the Issuer, or the Securities and Exchange Commission staff, upon request, information regarding the number of shares sold at each price within the range.

F3 · balance_after: Includes 12,933 restricted stock units ("RSUs") granted to the reporting person. Each RSU represents a contingent right to receive one share of Class A common stock. The unvested portion of the RSUs granted on March 11, 2022 vests on March 11, 2025, subject to the terms of the associated Participant Restricted Stock Unit Agreement. The unvested portion of the RSUs granted on March 10, 2023 vests in two equal installments on March 10, 2025 and March 10, 2026, subject to the terms of the associated Participant Restricted Stock Unit Agreement. The unvested portion of the RSUs granted on March 7, 2024 vests in three equal installments on March 7, 2025, March 7, 2026 and March 7, 2027, subject to the terms of the associated Participant Restricted Stock Unit Agreement.

SEC source: 0001856525-24-000040 · wk-form4_1711488074.xml · nonDerivative · entry 3

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 62,933

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F4 · kind: On March 22, 2024, pursuant to the terms of an exchange agreement, dated as of July 22, 2021 (as amended, the "Exchange Agreement"), 49,940 shares of Class B common stock of the Issuer ("Class B common stock") and limited partnership interests of Core & Main Holdings, LP (together, a "Paired Interest") were exchanged for shares of Class A common stock, on a one-for-one basis.

F5 · shares: On March 22, 2024, pursuant to the terms of the LLC Agreement, 49,940 vested Units held directly by the reporting person were redeemed at the discretion of the reporting person for 49,940 Paired Interests.

F3 · balance_after: Includes 12,933 restricted stock units ("RSUs") granted to the reporting person. Each RSU represents a contingent right to receive one share of Class A common stock. The unvested portion of the RSUs granted on March 11, 2022 vests on March 11, 2025, subject to the terms of the associated Participant Restricted Stock Unit Agreement. The unvested portion of the RSUs granted on March 10, 2023 vests in two equal installments on March 10, 2025 and March 10, 2026, subject to the terms of the associated Participant Restricted Stock Unit Agreement. The unvested portion of the RSUs granted on March 7, 2024 vests in three equal installments on March 7, 2025, March 7, 2026 and March 7, 2027, subject to the terms of the associated Participant Restricted Stock Unit Agreement.

SEC source: 0001856525-24-000040 · wk-form4_1711488074.xml · nonDerivative · entry 2

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,993

F1 · shares: On March 22, 2024, pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Core & Main Management Feeder, LLC ("Management Feeder"), dated as of July 22, 2021 (as amended, the "LLC Agreement"), 60 vested common units ("Units") held directly by the reporting person were redeemed at the discretion of the reporting person for 60 shares of Class A common stock of the Issuer ("Class A common stock").

F3 · balance_after: Includes 12,933 restricted stock units ("RSUs") granted to the reporting person. Each RSU represents a contingent right to receive one share of Class A common stock. The unvested portion of the RSUs granted on March 11, 2022 vests on March 11, 2025, subject to the terms of the associated Participant Restricted Stock Unit Agreement. The unvested portion of the RSUs granted on March 10, 2023 vests in two equal installments on March 10, 2025 and March 10, 2026, subject to the terms of the associated Participant Restricted Stock Unit Agreement. The unvested portion of the RSUs granted on March 7, 2024 vests in three equal installments on March 7, 2025, March 7, 2026 and March 7, 2027, subject to the terms of the associated Participant Restricted Stock Unit Agreement.

SEC source: 0001856525-24-000040 · wk-form4_1711488074.xml · nonDerivative · entry 1

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Indirect · By LLC

Disclosed balance after: 0

F1 · shares: On March 22, 2024, pursuant to the terms of the Fourth Amended and Restated LLC Agreement of Core & Main Management Feeder, LLC ("Management Feeder"), dated as of July 22, 2021 (as amended, the "LLC Agreement"), 60 vested common units ("Units") held directly by the reporting person were redeemed at the discretion of the reporting person for 60 shares of Class A common stock of the Issuer ("Class A common stock").

F2 · ownership.direct: Represents securities held by Management Feeder in respect of Units directly held by the reporting person. Pursuant to the LLC Agreement, such vested Units held by the reporting person are redeemable at the discretion of the reporting person for shares of Class A common stock, on a one-for-one basis.

SEC source: 0001856525-25-000009 · wk-form4_1736900234.xml · nonDerivative · entry 3

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 11,215

F1 · kind: Represents prior share forfeitures to the Issuer for tax withholding purposes upon the vesting of a portion of restricted stock units ("RSUs") granted to the reporting person.

F2 · balance_after: Of the 12,933 RSUs originally granted an aggregate of 1,718 shares of Class A common stock have been forfeited to the Issuer for tax withholdings purposes and an aggregate of 3,548 shares of Class A common stock have vested and sold with 7,667 RSUs remaining unvested, as of the date of this Form 4. Each RSU represents a contingent right to receive one share of Class A common stock. The unvested portion of the RSUs granted on March 11, 2022 vest on March 11, 2025. The RSUs granted on March 10, 2023 vest in two equal installments on March 10, 2025 and March 10, 2026. The RSUs granted on March 7, 2024 vest in three equal installments on March 7, 2025, March 7, 2026 and March 7, 2027. All RSU vesting is subject to the terms of the associated Participant Restricted Stock Unit Agreement.

SEC source: 0001856525-25-000009 · wk-form4_1736900234.xml · nonDerivative · entry 2

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 11,724

F1 · kind: Represents prior share forfeitures to the Issuer for tax withholding purposes upon the vesting of a portion of restricted stock units ("RSUs") granted to the reporting person.

F2 · balance_after: Of the 12,933 RSUs originally granted an aggregate of 1,718 shares of Class A common stock have been forfeited to the Issuer for tax withholdings purposes and an aggregate of 3,548 shares of Class A common stock have vested and sold with 7,667 RSUs remaining unvested, as of the date of this Form 4. Each RSU represents a contingent right to receive one share of Class A common stock. The unvested portion of the RSUs granted on March 11, 2022 vest on March 11, 2025. The RSUs granted on March 10, 2023 vest in two equal installments on March 10, 2025 and March 10, 2026. The RSUs granted on March 7, 2024 vest in three equal installments on March 7, 2025, March 7, 2026 and March 7, 2027. All RSU vesting is subject to the terms of the associated Participant Restricted Stock Unit Agreement.

SEC source: 0001856525-24-000031 · wk-form4_1710205943.xml · derivative · entry 3

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 18,999

Underlying: Class A Common Stock · 18,999 shares

Expires 2034-03-07

F4 · derivative.exercise_date: The options vest in three equal installments on March 7, 2025, March 7, 2026 and March 7, 2027, subject to the terms of the associated Participant Stock Option Agreement.

SEC source: 0001856525-24-000031 · wk-form4_1710205943.xml · nonDerivative · entry 1

Whittenburg Mark G · CIK 0001866737 · General Counsel and Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,933

F1 · shares: Represents restricted stock units ("RSUs") granted to the reporting person. Each RSU represents a contingent right to receive one share of Class A common stock of the Issuer ("Class A common stock"). The RSUs vest in three equal annual installments on March 7, 2025, March 7, 2026 and March 7, 2027, subject to the terms of the associated Participant Restricted Stock Unit Agreement.

F2 · balance_after: Includes RSUs previously granted to the reporting person.