QMCO

SEC source: 0001628280-20-003829 · wf-form4_158465023374317.xml · derivative · entry 3

Moorehead Lewis W. · CIK 0001597383 · Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 32,000

Underlying: Common Stock · 16,000 shares

Expires 2029-09-06

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.

F2 · derivative.exercise_price: Performance-Based Restricted Stock Units were previously reported on September 10, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any hundred (100) calendar day period, and upon specified service dates, whichever is later. The first achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 16,000 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on September 5, 2020, subject to continued employment. These shares are reflected on Table I, and 32,000 units remaining subject to these performance-based and time-based vesting conditions.

F2 · derivative.exercise_date: Performance-Based Restricted Stock Units were previously reported on September 10, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any hundred (100) calendar day period, and upon specified service dates, whichever is later. The first achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 16,000 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on September 5, 2020, subject to continued employment. These shares are reflected on Table I, and 32,000 units remaining subject to these performance-based and time-based vesting conditions.

SEC source: 0001628280-20-003829 · wf-form4_158465023374317.xml · derivative · entry 2

Moorehead Lewis W. · CIK 0001597383 · Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 16,666 shares

Expires 2022-06-01

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 · derivative.exercise_price: Performance-Based Restricted Stock Units were previously reported on October 2, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The third achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 16,666 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on May 31, 2021, subject to continued employment. These shares are reflected on Table I, and no units remain subject to these performance-based and time-based vesting conditions.

F1 · derivative.exercise_date: Performance-Based Restricted Stock Units were previously reported on October 2, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The third achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 16,666 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on May 31, 2021, subject to continued employment. These shares are reflected on Table I, and no units remain subject to these performance-based and time-based vesting conditions.

SEC source: 0001628280-20-003829 · wf-form4_158465023374317.xml · nonDerivative · entry 1

Moorehead Lewis W. · CIK 0001597383 · Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 134,331

F1 · security: Performance-Based Restricted Stock Units were previously reported on October 2, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The third achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 16,666 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on May 31, 2021, subject to continued employment. These shares are reflected on Table I, and no units remain subject to these performance-based and time-based vesting conditions.

F2 · security: Performance-Based Restricted Stock Units were previously reported on September 10, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any hundred (100) calendar day period, and upon specified service dates, whichever is later. The first achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 16,000 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on September 5, 2020, subject to continued employment. These shares are reflected on Table I, and 32,000 units remaining subject to these performance-based and time-based vesting conditions.

SEC source: 0001628280-20-003828 · wf-form4_158465020592549.xml · derivative · entry 3

DODSON J MICHAEL · CIK 0001231559 · Senior Vice President, CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 160,000

Underlying: Common Stock · 80,000 shares

Expires 2029-09-06

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.

F2 · derivative.exercise_price: Performance-Based Restricted Stock Units were previously reported on September 10, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any hundred (100) calendar day period, and upon specified service dates, whichever is later. The first performance achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 80,000 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on September 5, 2020 subject to continued employment. These shares are reflected on Table I, and 160,000 units remaining subject to these performance-based and time-based vesting conditions

F2 · derivative.exercise_date: Performance-Based Restricted Stock Units were previously reported on September 10, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any hundred (100) calendar day period, and upon specified service dates, whichever is later. The first performance achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 80,000 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on September 5, 2020 subject to continued employment. These shares are reflected on Table I, and 160,000 units remaining subject to these performance-based and time-based vesting conditions

SEC source: 0001628280-20-003828 · wf-form4_158465020592549.xml · derivative · entry 2

DODSON J MICHAEL · CIK 0001231559 · Senior Vice President, CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 41,666 shares

Expires 2022-06-01

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 · derivative.exercise_price: Performance-Based Restricted Stock Units were previously reported on August 27, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The third performance achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 41,666 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on May 31, 2021, subject to continued employment. These shares are reflected on Table I, and no units remain that are subject to these performance-based and time-based vesting conditions.

F1 · derivative.exercise_date: Performance-Based Restricted Stock Units were previously reported on August 27, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The third performance achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 41,666 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on May 31, 2021, subject to continued employment. These shares are reflected on Table I, and no units remain that are subject to these performance-based and time-based vesting conditions.

SEC source: 0001628280-20-003828 · wf-form4_158465020592549.xml · nonDerivative · entry 1

DODSON J MICHAEL · CIK 0001231559 · Senior Vice President, CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 444,577

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 · security: Performance-Based Restricted Stock Units were previously reported on August 27, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The third performance achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 41,666 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on May 31, 2021, subject to continued employment. These shares are reflected on Table I, and no units remain that are subject to these performance-based and time-based vesting conditions.

F2 · security: Performance-Based Restricted Stock Units were previously reported on September 10, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any hundred (100) calendar day period, and upon specified service dates, whichever is later. The first performance achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 80,000 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on September 5, 2020 subject to continued employment. These shares are reflected on Table I, and 160,000 units remaining subject to these performance-based and time-based vesting conditions

SEC source: 0001628280-20-003827 · wf-form4_158465018138052.xml · derivative · entry 2

Martella Donald E. Jr. · CIK 0001649891 · SVP, Engineering

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 42,667

Underlying: Common Stock · 21,333 shares

Expires 2029-09-06

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 · derivative.exercise_price: Performance-Based Restricted Stock Units were previously reported on September 10, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any hundred (100) calendar day period, and upon specified service dates, whichever is later. The first achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 21,333 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on September 5, 2020, subject to continued employment. These shares are reflected on Table I, and 42,667 units remain subject to these performance-based and time-based vesting conditions.

F1 · derivative.exercise_date: Performance-Based Restricted Stock Units were previously reported on September 10, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any hundred (100) calendar day period, and upon specified service dates, whichever is later. The first achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 21,333 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on September 5, 2020, subject to continued employment. These shares are reflected on Table I, and 42,667 units remain subject to these performance-based and time-based vesting conditions.

SEC source: 0001628280-20-003827 · wf-form4_158465018138052.xml · nonDerivative · entry 1

Martella Donald E. Jr. · CIK 0001649891 · SVP, Engineering

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 50,838

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 · security: Performance-Based Restricted Stock Units were previously reported on September 10, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any hundred (100) calendar day period, and upon specified service dates, whichever is later. The first achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 21,333 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on September 5, 2020, subject to continued employment. These shares are reflected on Table I, and 42,667 units remain subject to these performance-based and time-based vesting conditions.

SEC source: 0001628280-20-003826 · wf-form4_158465015782634.xml · derivative · entry 2

MacPherson Regan J · CIK 0001651155 · SVP, General Counsel

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 40,000

Underlying: Common Stock · 20,000 shares

Expires 2029-11-01

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 · derivative.exercise_price: Performance-Based Restricted Stock Units were previously reported on February 4, 2020, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any hundred (100) calendar day period, and upon specified service dates, whichever is later. The first achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 20,000 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on November 1, 2020, subject to continued employment. These shares are reflected on Table I, and 40,000 units remain subject to these performance-based and time-based vesting conditions.

F1 · derivative.exercise_date: Performance-Based Restricted Stock Units were previously reported on February 4, 2020, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any hundred (100) calendar day period, and upon specified service dates, whichever is later. The first achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 20,000 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on November 1, 2020, subject to continued employment. These shares are reflected on Table I, and 40,000 units remain subject to these performance-based and time-based vesting conditions.

SEC source: 0001628280-20-003826 · wf-form4_158465015782634.xml · nonDerivative · entry 1

MacPherson Regan J · CIK 0001651155 · SVP, General Counsel

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 35,000

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 · security: Performance-Based Restricted Stock Units were previously reported on February 4, 2020, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any hundred (100) calendar day period, and upon specified service dates, whichever is later. The first achievement date occurred on March 17, 2020, as certified by the leadership and compensation committee of QMCO, resulting in 20,000 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on November 1, 2020, subject to continued employment. These shares are reflected on Table I, and 40,000 units remain subject to these performance-based and time-based vesting conditions.

SEC source: 0001213900-20-006698 · ownership.xml · nonDerivative · entry 2

B. Riley Financial, Inc. · CIK 0001464790 · 10% owner

BRC Partners Opportunity Fund, LP · CIK 0001642765 · 10% owner

BRC Partners Management GP, LLC · CIK 0001749420 · 10% owner

B. RILEY CAPITAL MANAGEMENT, LLC · CIK 0001658704 · 10% owner

B. Riley FBR, Inc. · CIK 0001505748 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See notes

Disclosed balance after: 7,733,387

F1 · ownership.nature: In addition to B. Riley Financial, Inc., a Delaware corporation ("BRF"), this Form 4 is being filed jointly by BRC Partners Opportunity Fund, L.P., a Delaware limited partnership ("BRPLP"), B. Riley Capital Management, LLC, a New York limited liability company ("BRCM"), BRC Partners Management GP, LLC, a Delaware limited liability company ("BRPGP"), and B. Riley FBR, Inc., a Delaware corporation ("BRFBR" and collectively, the "Filing Persons").

F2 · ownership.nature: BRPGP is a subsidiary of BRCM, a registered investment advisor, and is the general partner of BRPLP. BRF is the parent company of BRCM. As a result, BRPGP, BRCM and BRF may be deemed to indirectly beneficially own the securities held by BRPLP. BRF is the parent company of BRFBR. As a result, BRF may be deemed to indirectly beneficially own the securities held by BRFBR. Each of the Filing Persons disclaims beneficial ownership of the outstanding shares of Common Stock ("Common Stock") of Quantum Corporation, a Delaware corporation (the "Issuer"), reported herein except to the extent of its pecuniary interest therein.

F3 · ownership.nature: Represents shares of Common Stock owned directly by BRFBR.

SEC source: 0001213900-20-006698 · ownership.xml · nonDerivative · entry 1

B. Riley Financial, Inc. · CIK 0001464790 · 10% owner

BRC Partners Opportunity Fund, LP · CIK 0001642765 · 10% owner

BRC Partners Management GP, LLC · CIK 0001749420 · 10% owner

B. RILEY CAPITAL MANAGEMENT, LLC · CIK 0001658704 · 10% owner

B. Riley FBR, Inc. · CIK 0001505748 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See notes

Disclosed balance after: 7,604,127

F5 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $2.48 to $3.10, inclusive. The Filing Persons reporting person undertakes to provide to the Commission, upon request, full information regarding the number of shares sold at each separate price.

F1 · ownership.nature: In addition to B. Riley Financial, Inc., a Delaware corporation ("BRF"), this Form 4 is being filed jointly by BRC Partners Opportunity Fund, L.P., a Delaware limited partnership ("BRPLP"), B. Riley Capital Management, LLC, a New York limited liability company ("BRCM"), BRC Partners Management GP, LLC, a Delaware limited liability company ("BRPGP"), and B. Riley FBR, Inc., a Delaware corporation ("BRFBR" and collectively, the "Filing Persons").

F2 · ownership.nature: BRPGP is a subsidiary of BRCM, a registered investment advisor, and is the general partner of BRPLP. BRF is the parent company of BRCM. As a result, BRPGP, BRCM and BRF may be deemed to indirectly beneficially own the securities held by BRPLP. BRF is the parent company of BRFBR. As a result, BRF may be deemed to indirectly beneficially own the securities held by BRFBR. Each of the Filing Persons disclaims beneficial ownership of the outstanding shares of Common Stock ("Common Stock") of Quantum Corporation, a Delaware corporation (the "Issuer"), reported herein except to the extent of its pecuniary interest therein.

F3 · ownership.nature: Represents shares of Common Stock owned directly by BRFBR.

SEC source: 0001213900-20-006043 · ownership.xml · nonDerivative · entry 6

B. Riley Financial, Inc. · CIK 0001464790 · 10% owner

BRC Partners Opportunity Fund, LP · CIK 0001642765 · 10% owner

BRC Partners Management GP, LLC · CIK 0001749420 · 10% owner

B. RILEY CAPITAL MANAGEMENT, LLC · CIK 0001658704 · 10% owner

B. Riley FBR, Inc. · CIK 0001505748 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See notes

Disclosed balance after: 5,216,824

F7 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $3.10 to $3.40, inclusive. The Filing Persons reporting person undertakes to provide to the Commission, upon request, full information regarding the number of shares sold at each separate price.

F4 · balance_after: Represents shares of Common Stock owned directly by BRFBR.

F1 · ownership.nature: In addition to B. Riley Financial, Inc., a Delaware corporation ("BRF"), this Form 4 is being filed jointly by BRC Partners Opportunity Fund, L.P., a Delaware limited partnership ("BRPLP"), B. Riley Capital Management, LLC, a New York limited liability company ("BRCM"), BRC Partners Management GP, LLC, a Delaware limited liability company ("BRPGP"), and B. Riley FBR, Inc., a Delaware corporation ("BRFBR" and collectively, the "Filing Persons").

F2 · ownership.nature: BRPGP is a subsidiary of BRCM, a registered investment advisor, and is the general partner of BRPLP. BRF is the parent company of BRCM. As a result, BRPGP, BRCM and BRF may be deemed to indirectly beneficially own the securities held by BRPLP. BRF is the parent company of BRFBR. As a result, BRF may be deemed to indirectly beneficially own the securities held by BRFBR. Each of the Filing Persons disclaims beneficial ownership of the outstanding shares of Common Stock ("Common Stock") of Quantum Corporation, a Delaware corporation (the "Issuer"), reported herein except to the extent of its pecuniary interest therein.

F4 · ownership.nature: Represents shares of Common Stock owned directly by BRFBR.

SEC source: 0001213900-20-006043 · ownership.xml · nonDerivative · entry 5

B. Riley Financial, Inc. · CIK 0001464790 · 10% owner

BRC Partners Opportunity Fund, LP · CIK 0001642765 · 10% owner

BRC Partners Management GP, LLC · CIK 0001749420 · 10% owner

B. RILEY CAPITAL MANAGEMENT, LLC · CIK 0001658704 · 10% owner

B. Riley FBR, Inc. · CIK 0001505748 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See notes

Disclosed balance after: 2,047,647

F3 · balance_after: Represents shares of Common Stock owned directly by BRPLP.

F1 · ownership.nature: In addition to B. Riley Financial, Inc., a Delaware corporation ("BRF"), this Form 4 is being filed jointly by BRC Partners Opportunity Fund, L.P., a Delaware limited partnership ("BRPLP"), B. Riley Capital Management, LLC, a New York limited liability company ("BRCM"), BRC Partners Management GP, LLC, a Delaware limited liability company ("BRPGP"), and B. Riley FBR, Inc., a Delaware corporation ("BRFBR" and collectively, the "Filing Persons").

F2 · ownership.nature: BRPGP is a subsidiary of BRCM, a registered investment advisor, and is the general partner of BRPLP. BRF is the parent company of BRCM. As a result, BRPGP, BRCM and BRF may be deemed to indirectly beneficially own the securities held by BRPLP. BRF is the parent company of BRFBR. As a result, BRF may be deemed to indirectly beneficially own the securities held by BRFBR. Each of the Filing Persons disclaims beneficial ownership of the outstanding shares of Common Stock ("Common Stock") of Quantum Corporation, a Delaware corporation (the "Issuer"), reported herein except to the extent of its pecuniary interest therein.

F3 · ownership.nature: Represents shares of Common Stock owned directly by BRPLP.

SEC source: 0001213900-20-006043 · ownership.xml · nonDerivative · entry 4

B. Riley Financial, Inc. · CIK 0001464790 · 10% owner

BRC Partners Opportunity Fund, LP · CIK 0001642765 · 10% owner

BRC Partners Management GP, LLC · CIK 0001749420 · 10% owner

B. RILEY CAPITAL MANAGEMENT, LLC · CIK 0001658704 · 10% owner

B. Riley FBR, Inc. · CIK 0001505748 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See notes

Disclosed balance after: 4,852,327

F6 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $3.75 to $3.90, inclusive. The Filing Persons reporting person undertakes to provide to the Commission, upon request, full information regarding the number of shares sold at each separate price.

F4 · balance_after: Represents shares of Common Stock owned directly by BRFBR.

F1 · ownership.nature: In addition to B. Riley Financial, Inc., a Delaware corporation ("BRF"), this Form 4 is being filed jointly by BRC Partners Opportunity Fund, L.P., a Delaware limited partnership ("BRPLP"), B. Riley Capital Management, LLC, a New York limited liability company ("BRCM"), BRC Partners Management GP, LLC, a Delaware limited liability company ("BRPGP"), and B. Riley FBR, Inc., a Delaware corporation ("BRFBR" and collectively, the "Filing Persons").

F2 · ownership.nature: BRPGP is a subsidiary of BRCM, a registered investment advisor, and is the general partner of BRPLP. BRF is the parent company of BRCM. As a result, BRPGP, BRCM and BRF may be deemed to indirectly beneficially own the securities held by BRPLP. BRF is the parent company of BRFBR. As a result, BRF may be deemed to indirectly beneficially own the securities held by BRFBR. Each of the Filing Persons disclaims beneficial ownership of the outstanding shares of Common Stock ("Common Stock") of Quantum Corporation, a Delaware corporation (the "Issuer"), reported herein except to the extent of its pecuniary interest therein.

F4 · ownership.nature: Represents shares of Common Stock owned directly by BRFBR.

SEC source: 0001213900-20-006043 · ownership.xml · nonDerivative · entry 3

B. Riley Financial, Inc. · CIK 0001464790 · 10% owner

BRC Partners Opportunity Fund, LP · CIK 0001642765 · 10% owner

BRC Partners Management GP, LLC · CIK 0001749420 · 10% owner

B. RILEY CAPITAL MANAGEMENT, LLC · CIK 0001658704 · 10% owner

B. Riley FBR, Inc. · CIK 0001505748 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See notes

Disclosed balance after: 1,693,801

F3 · balance_after: Represents shares of Common Stock owned directly by BRPLP.

F1 · ownership.nature: In addition to B. Riley Financial, Inc., a Delaware corporation ("BRF"), this Form 4 is being filed jointly by BRC Partners Opportunity Fund, L.P., a Delaware limited partnership ("BRPLP"), B. Riley Capital Management, LLC, a New York limited liability company ("BRCM"), BRC Partners Management GP, LLC, a Delaware limited liability company ("BRPGP"), and B. Riley FBR, Inc., a Delaware corporation ("BRFBR" and collectively, the "Filing Persons").

F2 · ownership.nature: BRPGP is a subsidiary of BRCM, a registered investment advisor, and is the general partner of BRPLP. BRF is the parent company of BRCM. As a result, BRPGP, BRCM and BRF may be deemed to indirectly beneficially own the securities held by BRPLP. BRF is the parent company of BRFBR. As a result, BRF may be deemed to indirectly beneficially own the securities held by BRFBR. Each of the Filing Persons disclaims beneficial ownership of the outstanding shares of Common Stock ("Common Stock") of Quantum Corporation, a Delaware corporation (the "Issuer"), reported herein except to the extent of its pecuniary interest therein.

F3 · ownership.nature: Represents shares of Common Stock owned directly by BRPLP.

SEC source: 0001213900-20-006043 · ownership.xml · nonDerivative · entry 2

B. Riley Financial, Inc. · CIK 0001464790 · 10% owner

BRC Partners Opportunity Fund, LP · CIK 0001642765 · 10% owner

BRC Partners Management GP, LLC · CIK 0001749420 · 10% owner

B. RILEY CAPITAL MANAGEMENT, LLC · CIK 0001658704 · 10% owner

B. Riley FBR, Inc. · CIK 0001505748 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See notes

Disclosed balance after: 4,706,727

F5 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $3.90 to $4.00, inclusive. The Filing Persons reporting person undertakes to provide to the Commission, upon request, full information regarding the number of shares sold at each separate price.

F4 · balance_after: Represents shares of Common Stock owned directly by BRFBR.

F1 · ownership.nature: In addition to B. Riley Financial, Inc., a Delaware corporation ("BRF"), this Form 4 is being filed jointly by BRC Partners Opportunity Fund, L.P., a Delaware limited partnership ("BRPLP"), B. Riley Capital Management, LLC, a New York limited liability company ("BRCM"), BRC Partners Management GP, LLC, a Delaware limited liability company ("BRPGP"), and B. Riley FBR, Inc., a Delaware corporation ("BRFBR" and collectively, the "Filing Persons").

F2 · ownership.nature: BRPGP is a subsidiary of BRCM, a registered investment advisor, and is the general partner of BRPLP. BRF is the parent company of BRCM. As a result, BRPGP, BRCM and BRF may be deemed to indirectly beneficially own the securities held by BRPLP. BRF is the parent company of BRFBR. As a result, BRF may be deemed to indirectly beneficially own the securities held by BRFBR. Each of the Filing Persons disclaims beneficial ownership of the outstanding shares of Common Stock ("Common Stock") of Quantum Corporation, a Delaware corporation (the "Issuer"), reported herein except to the extent of its pecuniary interest therein.

F4 · ownership.nature: Represents shares of Common Stock owned directly by BRFBR.

SEC source: 0001213900-20-006043 · ownership.xml · nonDerivative · entry 1

B. Riley Financial, Inc. · CIK 0001464790 · 10% owner

BRC Partners Opportunity Fund, LP · CIK 0001642765 · 10% owner

BRC Partners Management GP, LLC · CIK 0001749420 · 10% owner

B. RILEY CAPITAL MANAGEMENT, LLC · CIK 0001658704 · 10% owner

B. Riley FBR, Inc. · CIK 0001505748 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See notes

Disclosed balance after: 1,543,801

F3 · balance_after: Represents shares of Common Stock owned directly by BRPLP.

F1 · ownership.nature: In addition to B. Riley Financial, Inc., a Delaware corporation ("BRF"), this Form 4 is being filed jointly by BRC Partners Opportunity Fund, L.P., a Delaware limited partnership ("BRPLP"), B. Riley Capital Management, LLC, a New York limited liability company ("BRCM"), BRC Partners Management GP, LLC, a Delaware limited liability company ("BRPGP"), and B. Riley FBR, Inc., a Delaware corporation ("BRFBR" and collectively, the "Filing Persons").

F2 · ownership.nature: BRPGP is a subsidiary of BRCM, a registered investment advisor, and is the general partner of BRPLP. BRF is the parent company of BRCM. As a result, BRPGP, BRCM and BRF may be deemed to indirectly beneficially own the securities held by BRPLP. BRF is the parent company of BRFBR. As a result, BRF may be deemed to indirectly beneficially own the securities held by BRFBR. Each of the Filing Persons disclaims beneficial ownership of the outstanding shares of Common Stock ("Common Stock") of Quantum Corporation, a Delaware corporation (the "Issuer"), reported herein except to the extent of its pecuniary interest therein.

F3 · ownership.nature: Represents shares of Common Stock owned directly by BRPLP.

SEC source: 0001213900-20-005074 · ownership.xml · nonDerivative · entry 1

B. Riley Financial, Inc. · CIK 0001464790 · 10% owner

BRC Partners Opportunity Fund, LP · CIK 0001642765 · 10% owner

BRC Partners Management GP, LLC · CIK 0001749420 · 10% owner

B. RILEY CAPITAL MANAGEMENT, LLC · CIK 0001658704 · 10% owner

B. Riley FBR, Inc. · CIK 0001505748 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See notes

Disclosed balance after: 4,656,262

F4 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $4.80 to $4.95, inclusive. The Filing Persons reporting person undertakes to provide to the Commission, upon request, full information regarding the number of shares sold at each separate price.

F1 · ownership.nature: In addition to B. Riley Financial, Inc., a Delaware corporation ("BRF"), this Form 4 is being filed jointly by BRC Partners Opportunity Fund, L.P., a Delaware limited partnership ("BRPLP"), B. Riley Capital Management, LLC, a New York limited liability company ("BRCM"), BRC Partners Management GP, LLC, a Delaware limited liability company ("BRPGP"), and B. Riley FBR, Inc., a Delaware corporation ("BRFBR" and collectively, the "Filing Persons").

F2 · ownership.nature: BRPGP is a subsidiary of BRCM, a registered investment advisor, and is the general partner of BRPLP. BRF is the parent company of BRCM. As a result, BRPGP, BRCM and BRF may be deemed to indirectly beneficially own the securities held by BRPLP. BRF is the parent company of BRFBR. As a result, BRF may be deemed to indirectly beneficially own the securities held by BRFBR. Each of the Filing Persons disclaims beneficial ownership of the outstanding shares of Common Stock ("Common Stock") of Quantum Corporation, a Delaware corporation (the "Issuer"), reported herein except to the extent of its pecuniary interest therein.

F3 · ownership.nature: Represents shares of Common Stock owned directly by BRFBR.

SEC source: 0000899243-20-005834 · doc4.xml · nonDerivative · entry 3

Martella Donald E. Jr. · CIK 0001649891 · SVP, ENGINEERING

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 22,838

SEC source: 0000899243-20-005834 · doc4.xml · nonDerivative · entry 2

Martella Donald E. Jr. · CIK 0001649891 · SVP, ENGINEERING

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 22,843

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $5.300 to $5.370, inclusive.

SEC source: 0000899243-20-005834 · doc4.xml · nonDerivative · entry 1

Martella Donald E. Jr. · CIK 0001649891 · SVP, ENGINEERING

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 38,957

F1 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $5.555 to $5.735, inclusive. The reporting person undertakes to provide to Quantum Corporation, any security holder of Quantum Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnotes (1) and (2) to this Form 4.

SEC source: 0000899243-20-002844 · doc4.xml · derivative · entry 2

MacPherson Regan J · CIK 0001651155 · See Remarks

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 60,000

Underlying: Common Stock · 60,000 shares

Expires 2029-02-03

F2 · derivative.exercise_price: Grant of Performance-Based Restricted Stock Units, each of which represents a contingent right to receive one share of common stock of QMCO, with vesting subject to the achievement of specified levels of the average closing prices of a share of QMCO common stock during any one hundred (100) day trading period. Vesting is subject to continued employment with the Company through the later of the achievement date or service vesting date, which occurs in three equal annual installments on November 1, 2020, November 1, 2021 and November 1, 2022.

F2 · derivative.exercise_date: Grant of Performance-Based Restricted Stock Units, each of which represents a contingent right to receive one share of common stock of QMCO, with vesting subject to the achievement of specified levels of the average closing prices of a share of QMCO common stock during any one hundred (100) day trading period. Vesting is subject to continued employment with the Company through the later of the achievement date or service vesting date, which occurs in three equal annual installments on November 1, 2020, November 1, 2021 and November 1, 2022.

SEC source: 0000899243-20-002844 · doc4.xml · nonDerivative · entry 1

MacPherson Regan J · CIK 0001651155 · See Remarks

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 15,000

F1 · security: Grant of Restricted Stock Units ("RSUs"), each of which represents a contingent right to receive one share of common stock of QMCO. The RSUs vest in three equal annual installments on November 1, 2020, November 1, 2021 and November 1, 2022, subject to continued employment.

SEC source: 0000899243-20-002837 · doc4.xml · nonDerivative · entry 1

Jacoby Rebecca · CIK 0001623506 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 15,770

F1 · security: Grant of Restricted Stock Units ("RSUs"), each of which represents a contingent right to receive one share of common stock of QMCO (the "Company"). The RSUs vest in full on the earlier of January 10, 2021 or the date of the Company's next annual stockholder meeting, subject to continued employment.

SEC source: 0001213900-20-002290 · ownership.xml · nonDerivative · entry 2

B. Riley Financial, Inc. · CIK 0001464790 · 10% owner

BRC Partners Opportunity Fund, LP · CIK 0001642765 · 10% owner

BRC Partners Management GP, LLC · CIK 0001749420 · 10% owner

B. RILEY CAPITAL MANAGEMENT, LLC · CIK 0001658704 · 10% owner

B. Riley FBR, Inc. · CIK 0001505748 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See notes

Disclosed balance after: 4,597,562

F3 · kind: This Form 4 is being filed voluntarily to reflect a mere change in form of beneficial ownership by BRF, which is exempt from Section 16 of the Exchange Act of 1934 pursuant to Rule 16a-13. On January 29, 2020, BRF sold 969,900 shares of Common Stock to BRFBR at a price of $8.35 per share. BRF previously reported that it may have been deemed to directly beneficially own the 969,900 shares of Common Stock sold to BRFBR. Following the sale, the form of BRF's beneficial ownership changed from direct to indirect.

F3 · price: This Form 4 is being filed voluntarily to reflect a mere change in form of beneficial ownership by BRF, which is exempt from Section 16 of the Exchange Act of 1934 pursuant to Rule 16a-13. On January 29, 2020, BRF sold 969,900 shares of Common Stock to BRFBR at a price of $8.35 per share. BRF previously reported that it may have been deemed to directly beneficially own the 969,900 shares of Common Stock sold to BRFBR. Following the sale, the form of BRF's beneficial ownership changed from direct to indirect.

F1 · ownership.nature: In addition to B. Riley Financial, Inc., a Delaware corporation ("BRF"), this Form 4 is being filed jointly by BRC Partners Opportunity Fund, L.P., a Delaware limited partnership ("BRPLP"), B. Riley Capital Management, LLC, a New York limited liability company ("BRCM"), BRC Partners Management GP, LLC, a Delaware limited liability company ("BRPGP") and B. Riley FBR, Inc., a Delaware corporation ("BRFBR" and collectively, the "Filing Persons").

F2 · ownership.nature: BRPGP is a subsidiary of BRCM, a registered investment advisor, and is the general partner of BRPLP. BRF is the parent company of BRCM. As a result, BRPGP, BRCM and BRF may be deemed to indirectly beneficially own the securities held by BRPLP. BRF is the parent company of BRFBR. As a result, BRF may be deemed to indirectly beneficially own the securities held by BRFBR. Each of the Filing Persons disclaims beneficial ownership of the outstanding shares of Common Stock ("Common Stock") of Quantum Corporation, a Delaware corporation (the "Issuer"), reported herein except to the extent of its pecuniary interest therein.

F4 · ownership.nature: Represents shares of Common Stock owned directly by BRFBR.

SEC source: 0001213900-20-002290 · ownership.xml · nonDerivative · entry 1

B. Riley Financial, Inc. · CIK 0001464790 · 10% owner

BRC Partners Opportunity Fund, LP · CIK 0001642765 · 10% owner

BRC Partners Management GP, LLC · CIK 0001749420 · 10% owner

B. RILEY CAPITAL MANAGEMENT, LLC · CIK 0001658704 · 10% owner

B. Riley FBR, Inc. · CIK 0001505748 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

F1 · security: In addition to B. Riley Financial, Inc., a Delaware corporation ("BRF"), this Form 4 is being filed jointly by BRC Partners Opportunity Fund, L.P., a Delaware limited partnership ("BRPLP"), B. Riley Capital Management, LLC, a New York limited liability company ("BRCM"), BRC Partners Management GP, LLC, a Delaware limited liability company ("BRPGP") and B. Riley FBR, Inc., a Delaware corporation ("BRFBR" and collectively, the "Filing Persons").

F2 · security: BRPGP is a subsidiary of BRCM, a registered investment advisor, and is the general partner of BRPLP. BRF is the parent company of BRCM. As a result, BRPGP, BRCM and BRF may be deemed to indirectly beneficially own the securities held by BRPLP. BRF is the parent company of BRFBR. As a result, BRF may be deemed to indirectly beneficially own the securities held by BRFBR. Each of the Filing Persons disclaims beneficial ownership of the outstanding shares of Common Stock ("Common Stock") of Quantum Corporation, a Delaware corporation (the "Issuer"), reported herein except to the extent of its pecuniary interest therein.

F3 · kind: This Form 4 is being filed voluntarily to reflect a mere change in form of beneficial ownership by BRF, which is exempt from Section 16 of the Exchange Act of 1934 pursuant to Rule 16a-13. On January 29, 2020, BRF sold 969,900 shares of Common Stock to BRFBR at a price of $8.35 per share. BRF previously reported that it may have been deemed to directly beneficially own the 969,900 shares of Common Stock sold to BRFBR. Following the sale, the form of BRF's beneficial ownership changed from direct to indirect.

F3 · price: This Form 4 is being filed voluntarily to reflect a mere change in form of beneficial ownership by BRF, which is exempt from Section 16 of the Exchange Act of 1934 pursuant to Rule 16a-13. On January 29, 2020, BRF sold 969,900 shares of Common Stock to BRFBR at a price of $8.35 per share. BRF previously reported that it may have been deemed to directly beneficially own the 969,900 shares of Common Stock sold to BRFBR. Following the sale, the form of BRF's beneficial ownership changed from direct to indirect.

SEC source: 0000921895-19-002984 · form410114016_12122019.xml · nonDerivative · entry 4

Singer Eric · CIK 0001443284 · 10% owner · See Explanation of Responses

VIEX Opportunities Fund, LP Series One · CIK 0001606750 · See Explanation of Responses

VIEX Opportunities Fund, LP - Series Two · CIK 0001659404 · See Explanation of Responses

VIEX Special Opportunities Fund III, LP · CIK 0001619126 · See Explanation of Responses

VIEX GP, LLC · CIK 0001654852 · See Explanation of Responses

VIEX Special Opportunities GP III, LLC · CIK 0001676049 · See Explanation of Responses

VIEX Capital Advisors, LLC · CIK 0001619125 · See Explanation of Responses

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Viex Special Opportunities Fund III, LP

Disclosed balance after: 2,336,364

F1 · security: This Form 4 is filed jointly by VIEX Opportunities Fund, LP - Series One ("Series One"), a series of VIEX Opportunities Fund, LP, VIEX Opportunities Fund, LP - Series Two ("Series Two"), a series of VIEX Opportunities Fund, LP, Viex Special Opportunities Fund III, LP ("VSO III"), VIEX GP, LLC ("VIEX GP"), Viex Special Opportunities GP III, LLC ("VSO GP III"), VIEX Capital Advisors, LLC ("VIEX Capital"), and Eric Singer (collectively, the "Reporting Persons").

F2 · security: As of the close of business on December 10, 2019, the Reporting Persons ceased to be holders of an aggregate of 10% or more of Quantum Corporation's (the "Issuer") outstanding shares of Common Stock. Each Reporting Person disclaims beneficial ownership of the securities of the Issuer reported herein except to the extent of his or its pecuniary interest therein, and this report shall not be deemed to be an admission that any Reporting Person is the beneficial owner of such securities for purposes of Section 16 or for any other purpose.

F6 · ownership.nature: Securities of the Issuer beneficially owned directly by VSO III. VSO GP III, as the general partner of VSO III, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by VSO III. VIEX Capital, as the investment manager of VSO III, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by VSO III. Mr. Singer, as the managing member of each of VSO GP III and VIEX Capital, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by VSO III.

SEC source: 0000921895-19-002984 · form410114016_12122019.xml · nonDerivative · entry 3

Singer Eric · CIK 0001443284 · 10% owner · See Explanation of Responses

VIEX Opportunities Fund, LP Series One · CIK 0001606750 · See Explanation of Responses

VIEX Opportunities Fund, LP - Series Two · CIK 0001659404 · See Explanation of Responses

VIEX Special Opportunities Fund III, LP · CIK 0001619126 · See Explanation of Responses

VIEX GP, LLC · CIK 0001654852 · See Explanation of Responses

VIEX Special Opportunities GP III, LLC · CIK 0001676049 · See Explanation of Responses

VIEX Capital Advisors, LLC · CIK 0001619125 · See Explanation of Responses

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Viex Opportunities Fund, LP - Series Two

Disclosed balance after: 159,421

F1 · security: This Form 4 is filed jointly by VIEX Opportunities Fund, LP - Series One ("Series One"), a series of VIEX Opportunities Fund, LP, VIEX Opportunities Fund, LP - Series Two ("Series Two"), a series of VIEX Opportunities Fund, LP, Viex Special Opportunities Fund III, LP ("VSO III"), VIEX GP, LLC ("VIEX GP"), Viex Special Opportunities GP III, LLC ("VSO GP III"), VIEX Capital Advisors, LLC ("VIEX Capital"), and Eric Singer (collectively, the "Reporting Persons").

F2 · security: As of the close of business on December 10, 2019, the Reporting Persons ceased to be holders of an aggregate of 10% or more of Quantum Corporation's (the "Issuer") outstanding shares of Common Stock. Each Reporting Person disclaims beneficial ownership of the securities of the Issuer reported herein except to the extent of his or its pecuniary interest therein, and this report shall not be deemed to be an admission that any Reporting Person is the beneficial owner of such securities for purposes of Section 16 or for any other purpose.

F5 · ownership.nature: Securities of the Issuer beneficially owned directly by Series Two. VIEX GP, as the general partner of Series Two, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by Series Two. VIEX Capital, as the investment manager of Series Two, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by Series Two. Mr. Singer, as the managing member of each of VIEX GP and VIEX Capital, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by Series Two.

SEC source: 0000921895-19-002984 · form410114016_12122019.xml · nonDerivative · entry 2

Singer Eric · CIK 0001443284 · 10% owner · See Explanation of Responses

VIEX Opportunities Fund, LP Series One · CIK 0001606750 · See Explanation of Responses

VIEX Opportunities Fund, LP - Series Two · CIK 0001659404 · See Explanation of Responses

VIEX Special Opportunities Fund III, LP · CIK 0001619126 · See Explanation of Responses

VIEX GP, LLC · CIK 0001654852 · See Explanation of Responses

VIEX Special Opportunities GP III, LLC · CIK 0001676049 · See Explanation of Responses

VIEX Capital Advisors, LLC · CIK 0001619125 · See Explanation of Responses

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Viex Opportunities Fund, LP - Series One

Disclosed balance after: 835,679

F1 · security: This Form 4 is filed jointly by VIEX Opportunities Fund, LP - Series One ("Series One"), a series of VIEX Opportunities Fund, LP, VIEX Opportunities Fund, LP - Series Two ("Series Two"), a series of VIEX Opportunities Fund, LP, Viex Special Opportunities Fund III, LP ("VSO III"), VIEX GP, LLC ("VIEX GP"), Viex Special Opportunities GP III, LLC ("VSO GP III"), VIEX Capital Advisors, LLC ("VIEX Capital"), and Eric Singer (collectively, the "Reporting Persons").

F2 · security: As of the close of business on December 10, 2019, the Reporting Persons ceased to be holders of an aggregate of 10% or more of Quantum Corporation's (the "Issuer") outstanding shares of Common Stock. Each Reporting Person disclaims beneficial ownership of the securities of the Issuer reported herein except to the extent of his or its pecuniary interest therein, and this report shall not be deemed to be an admission that any Reporting Person is the beneficial owner of such securities for purposes of Section 16 or for any other purpose.

F4 · ownership.nature: Securities of the Issuer beneficially owned directly by Series One. VIEX GP, as the general partner of Series One, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by Series One. VIEX Capital, as the investment manager of Series One, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by Series One. Mr. Singer, as the managing member of each of VIEX GP and VIEX Capital, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by Series One.

SEC source: 0000899243-19-028599 · doc4.xml · nonDerivative · entry 1

FICHTHORN JOHN · CIK 0001411509 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · Held by Dialectic Antithesis Partners, LP

Disclosed balance after: 0

F1 · security: On December 3, 2019, Dialectic Antithesis Partners, LP crossed 969,900 shares of QMCO Common Stock to its affiliate, B. Riley Financial, Inc., its ultimate parent company.

F2 · ownership.nature: BR Dialectic Capital Management, LLC is the investment manager of Dialectic Antithesis Partners, LP and, as such, shares voting and dispositive power over the securities held by Dialectic Antithesis Partners, LP. The Reporting Person is a portfolio manager for BR Dialectic Capital Management, LLC and therefore shares voting and dispositive power over the securities, but the Reporting Person disclaims beneficial ownership of any of QMCO's securities in which he does not have a pecuniary interest or that he does not directly own. BR Dialectic Capital Management, LLC is a wholly owned subsidiary of B. Riley Financial, Inc., a publicly traded Delaware corporation (Nasdaq: RILY). B. Riley Financial, Inc. is the holder of the reported securities as a result of the reported transaction.

SEC source: 0001213900-19-025434 · ownership.xml · nonDerivative · entry 1

BR Dialectic Capital Management, LLC · CIK 0001704985 · 10% owner

Dialectic Antithesis Partners, LP · CIK 0001325552 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · Held by Dialectic Antithesis Partners, LP

Disclosed balance after: 0

F1 · ownership.nature: In addition to BR Dialectic Capital Management, LLC, a Delaware limited liability company ("BR Dialectic"), this Form 4 is being filed jointly by Dialectic Antithesis Partners, LP, a Delaware limited partnership ("Dialectic" and collectively, the "Filing Persons").

F2 · ownership.nature: BR Dialectic is the general partner and investment manager of Dialectic. As a result, BR Dialectic may be deemed to indirectly beneficially own the securities held by Dialectic. Each of the Filing Persons disclaims beneficial ownership of the outstanding shares of Common Stock ("Common Stock") of Quantum Corporation, a Delaware corporation (the "Issuer"), reported herein except to the extent of its pecuniary interest therein.

F3 · ownership.nature: On December 3, 2019, B. Riley Financial, Inc. ("BRF") purchased 969,900 shares of Common Stock from Dialectic at a purchase price of $5.25 per share. BRF previously reported that it may have been deemed to indirectly beneficially own the 969,900 shares of Common Stock that were previously held by Dialectic. As a result of the sale, the Filing Persons do not own any shares of Common Stock and are no longer subject to Section 16 of the Exchange Act of 1934.

SEC source: 0001213900-19-025436 · ownership.xml · nonDerivative · entry 1

B. Riley Financial, Inc. · CIK 0001464790 · 10% owner

BRC Partners Opportunity Fund, LP · CIK 0001642765 · 10% owner

BRC Partners Management GP, LLC · CIK 0001749420 · 10% owner

B. RILEY CAPITAL MANAGEMENT, LLC · CIK 0001658704 · 10% owner

B. Riley FBR, Inc. · CIK 0001505748 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 969,900

F1 · security: In addition to B. Riley Financial, Inc., a Delaware corporation ("BRF"), this Form 4 is being filed jointly by BRC Partners Opportunity Fund, L.P., a Delaware limited partnership ("BRPLP"), B. Riley Capital Management, LLC, a New York limited liability company ("BRCM"), BRC Partners Management GP, LLC, a Delaware limited liability company ("BRPGP") and B. Riley FBR, Inc., a Delaware corporation ("BRFBR" and collectively, the "Filing Persons").

F2 · security: BRPGP is a subsidiary of BRCM, a registered investment advisor, and is the general partner of BRPLP. BRF is the parent company of BRCM. As a result, BRPGP, BRCM and BRF may be deemed to indirectly beneficially own the securities held by BRPLP. BRF is the parent company of BRFBR. As a result, BRF may be deemed to indirectly beneficially own the securities held by BRFBR. Each of the Filing Persons disclaims beneficial ownership of the outstanding shares of Common Stock ("Common Stock") of Quantum Corporation, a Delaware corporation (the "Issuer"), reported herein except to the extent of its pecuniary interest therein.

F3 · kind: This Form 4 is being filed voluntarily to reflect a mere change in form of beneficial ownership by BRF, which is exempt from Section 16 of the Exchange Act of 1934 pursuant to Rule 16a-13. On December 3, 2019, BRF purchased 969,900 shares of Common Stock from Dialectic Antithesis Partners, LP ("Dialectic") at a purchase price of $5.25 per share. BRF previously reported that it may have been deemed to indirectly beneficially own the 969,900 shares of Common Stock that were previously held by Dialectic. Following the purchase, the form of BRF's beneficial ownership changed from indirect to direct.

F3 · price: This Form 4 is being filed voluntarily to reflect a mere change in form of beneficial ownership by BRF, which is exempt from Section 16 of the Exchange Act of 1934 pursuant to Rule 16a-13. On December 3, 2019, BRF purchased 969,900 shares of Common Stock from Dialectic Antithesis Partners, LP ("Dialectic") at a purchase price of $5.25 per share. BRF previously reported that it may have been deemed to indirectly beneficially own the 969,900 shares of Common Stock that were previously held by Dialectic. Following the purchase, the form of BRF's beneficial ownership changed from indirect to direct.

SEC source: 0000899243-19-027356 · doc4.xml · derivative · entry 2

Moorehead Lewis W. · CIK 0001597383 · Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 16,666

Underlying: Common Stock · 16,667 shares

Expires 2029-11-13

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 · derivative.exercise_price: Performance-Based Restricted Stock Units were previously reported on October 2, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The second achievement date occurred on November 13, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 16,667 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on May 31, 2020, subject to continued employment. These shares are reflected on Table I, and 16,666 units remaining subject to performance-based and time-based vesting conditions.

F1 · derivative.exercise_date: Performance-Based Restricted Stock Units were previously reported on October 2, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The second achievement date occurred on November 13, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 16,667 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on May 31, 2020, subject to continued employment. These shares are reflected on Table I, and 16,666 units remaining subject to performance-based and time-based vesting conditions.

SEC source: 0000899243-19-027356 · doc4.xml · nonDerivative · entry 1

Moorehead Lewis W. · CIK 0001597383 · Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 101,665

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 · security: Performance-Based Restricted Stock Units were previously reported on October 2, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The second achievement date occurred on November 13, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 16,667 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on May 31, 2020, subject to continued employment. These shares are reflected on Table I, and 16,666 units remaining subject to performance-based and time-based vesting conditions.

SEC source: 0000899243-19-027354 · doc4.xml · derivative · entry 2

King Elizabeth · CIK 0001770712 · CHIEF REVENUE OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 50,000

Underlying: Common Stock · 50,000 shares

Expires 2029-11-13

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 · derivative.exercise_price: Performance-Based Restricted Stock Units were previously reported on October 2, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The second achievement date occurred on November 13, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 50,000 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on May 31, 2020, subject to continued employment. These shares are reflected on Table I, and 50,000 units remaining subject to performance-based and time-based vesting conditions.

F1 · derivative.exercise_date: Performance-Based Restricted Stock Units were previously reported on October 2, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The second achievement date occurred on November 13, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 50,000 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on May 31, 2020, subject to continued employment. These shares are reflected on Table I, and 50,000 units remaining subject to performance-based and time-based vesting conditions.

SEC source: 0000899243-19-027354 · doc4.xml · nonDerivative · entry 1

King Elizabeth · CIK 0001770712 · CHIEF REVENUE OFFICER

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 250,000

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 · security: Performance-Based Restricted Stock Units were previously reported on October 2, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The second achievement date occurred on November 13, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 50,000 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on May 31, 2020, subject to continued employment. These shares are reflected on Table I, and 50,000 units remaining subject to performance-based and time-based vesting conditions.

SEC source: 0000899243-19-027359 · doc4.xml · derivative · entry 2

DODSON J MICHAEL · CIK 0001231559 · See Remarks

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 41,666

Underlying: Common Stock · 41,667 shares

Expires 2029-11-13

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 · derivative.exercise_price: Performance-Based Restricted Stock Units were previously reported on August 27, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The second performance achievement date occurred on November 13, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 41,667 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on June 1, 2020, subject to continued employment. These shares are reflected on Table I, and 41,666 units remaining subject to performance-based and time-based vesting conditions.

F1 · derivative.exercise_date: Performance-Based Restricted Stock Units were previously reported on August 27, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The second performance achievement date occurred on November 13, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 41,667 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on June 1, 2020, subject to continued employment. These shares are reflected on Table I, and 41,666 units remaining subject to performance-based and time-based vesting conditions.

SEC source: 0000899243-19-027359 · doc4.xml · nonDerivative · entry 1

DODSON J MICHAEL · CIK 0001231559 · See Remarks

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 322,911

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 · security: Performance-Based Restricted Stock Units were previously reported on August 27, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The second performance achievement date occurred on November 13, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 41,667 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on June 1, 2020, subject to continued employment. These shares are reflected on Table I, and 41,666 units remaining subject to performance-based and time-based vesting conditions.

SEC source: 0000899243-19-027357 · doc4.xml · derivative · entry 2

Lerner James J · CIK 0001602567 · Director · President, CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 150,000

Underlying: Common Stock · 150,000 shares

Expires 2029-11-13

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 · derivative.exercise_price: Performance-Based Restricted Stock Units were previously reported on August 27, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The second achievement date occurred on November 13,2019, as certified by the leadership and compensation committee of QMCO, resulting in 150,000 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on July 1, 2020, subject to continued employment. These shares are reflected on Table I, and 150,000 units remaining subject to performance-based and time-based vesting conditions.

F1 · derivative.exercise_date: Performance-Based Restricted Stock Units were previously reported on August 27, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The second achievement date occurred on November 13,2019, as certified by the leadership and compensation committee of QMCO, resulting in 150,000 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on July 1, 2020, subject to continued employment. These shares are reflected on Table I, and 150,000 units remaining subject to performance-based and time-based vesting conditions.

SEC source: 0000899243-19-027357 · doc4.xml · nonDerivative · entry 1

Lerner James J · CIK 0001602567 · Director · President, CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 930,000

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 · security: Performance-Based Restricted Stock Units were previously reported on August 27, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The second achievement date occurred on November 13,2019, as certified by the leadership and compensation committee of QMCO, resulting in 150,000 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest on July 1, 2020, subject to continued employment. These shares are reflected on Table I, and 150,000 units remaining subject to performance-based and time-based vesting conditions.

SEC source: 0000899243-19-025111 · doc4.xml · derivative · entry 4

Moorehead Lewis W. · CIK 0001597383 · Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 33,333

Underlying: Common Stock · 16,667 shares

Expires 2029-10-02

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.

F2 · derivative.exercise_price: Grant of 50,000 Performance-Based Restricted Stock Units, each of which represents a contingent right to receive one share of common stock of QMCO, with vesting subject to the achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022. Vesting is subject to continued employment with the Company through the later of the achievement date or service vesting date, which occurs in three equal annual installments on May 31, 2019, May 31, 2020 and May 31, 2021. The first achievement date occurred on October 2, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 16,667 units vesting, as reflected on Table I, and 33,333 units remaining subject to performance-based and time-based vesting conditions.

F2 · derivative.exercise_date: Grant of 50,000 Performance-Based Restricted Stock Units, each of which represents a contingent right to receive one share of common stock of QMCO, with vesting subject to the achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022. Vesting is subject to continued employment with the Company through the later of the achievement date or service vesting date, which occurs in three equal annual installments on May 31, 2019, May 31, 2020 and May 31, 2021. The first achievement date occurred on October 2, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 16,667 units vesting, as reflected on Table I, and 33,333 units remaining subject to performance-based and time-based vesting conditions.

SEC source: 0000899243-19-025111 · doc4.xml · derivative · entry 3

Moorehead Lewis W. · CIK 0001597383 · Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 50,000

Underlying: Common Stock · 50,000 shares

Expires 2029-10-02

F2 · derivative.exercise_price: Grant of 50,000 Performance-Based Restricted Stock Units, each of which represents a contingent right to receive one share of common stock of QMCO, with vesting subject to the achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022. Vesting is subject to continued employment with the Company through the later of the achievement date or service vesting date, which occurs in three equal annual installments on May 31, 2019, May 31, 2020 and May 31, 2021. The first achievement date occurred on October 2, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 16,667 units vesting, as reflected on Table I, and 33,333 units remaining subject to performance-based and time-based vesting conditions.

F2 · derivative.exercise_date: Grant of 50,000 Performance-Based Restricted Stock Units, each of which represents a contingent right to receive one share of common stock of QMCO, with vesting subject to the achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022. Vesting is subject to continued employment with the Company through the later of the achievement date or service vesting date, which occurs in three equal annual installments on May 31, 2019, May 31, 2020 and May 31, 2021. The first achievement date occurred on October 2, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 16,667 units vesting, as reflected on Table I, and 33,333 units remaining subject to performance-based and time-based vesting conditions.

SEC source: 0000899243-19-025111 · doc4.xml · nonDerivative · entry 2

Moorehead Lewis W. · CIK 0001597383 · Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 84,998

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.

F2 · security: Grant of 50,000 Performance-Based Restricted Stock Units, each of which represents a contingent right to receive one share of common stock of QMCO, with vesting subject to the achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022. Vesting is subject to continued employment with the Company through the later of the achievement date or service vesting date, which occurs in three equal annual installments on May 31, 2019, May 31, 2020 and May 31, 2021. The first achievement date occurred on October 2, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 16,667 units vesting, as reflected on Table I, and 33,333 units remaining subject to performance-based and time-based vesting conditions.

SEC source: 0000899243-19-025111 · doc4.xml · nonDerivative · entry 1

Moorehead Lewis W. · CIK 0001597383 · Chief Accounting Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 68,331

F1 · security: Grant of Restricted Stock Units ("RSUs"), each of which represents a contingent right to receive one share of common stock of QMCO. The RSUs vest in three equal annual installments on November 1, 2019, November 1, 2020 and November 1, 2021, subject to continued employment.

SEC source: 0000899243-19-025105 · doc4.xml · derivative · entry 4

King Elizabeth · CIK 0001770712 · Chief Revenue Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 100,000

Underlying: Common Stock · 50,000 shares

Expires 2029-10-02

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.

F2 · derivative.exercise_price: Grant of 150,000 Performance-Based Restricted Stock Units, each of which represents a contingent right to receive one share of common stock of QMCO, with vesting subject to the achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022. Vesting is subject to continued employment with the Company through the later of the achievement date or service vesting date, which occurs in three equal annual installments on May 31, 2019, May 31, 2020 and May 31, 2021. The first achievement date occurred on October 2, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 50,000 units vesting, as reflected on Table I, and 100,000 units remaining subject to performance-based and time-based vesting conditions.

F2 · derivative.exercise_date: Grant of 150,000 Performance-Based Restricted Stock Units, each of which represents a contingent right to receive one share of common stock of QMCO, with vesting subject to the achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022. Vesting is subject to continued employment with the Company through the later of the achievement date or service vesting date, which occurs in three equal annual installments on May 31, 2019, May 31, 2020 and May 31, 2021. The first achievement date occurred on October 2, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 50,000 units vesting, as reflected on Table I, and 100,000 units remaining subject to performance-based and time-based vesting conditions.

SEC source: 0000899243-19-025105 · doc4.xml · derivative · entry 3

King Elizabeth · CIK 0001770712 · Chief Revenue Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 150,000

Underlying: Common Stock · 150,000 shares

Expires 2029-10-02

F2 · derivative.exercise_price: Grant of 150,000 Performance-Based Restricted Stock Units, each of which represents a contingent right to receive one share of common stock of QMCO, with vesting subject to the achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022. Vesting is subject to continued employment with the Company through the later of the achievement date or service vesting date, which occurs in three equal annual installments on May 31, 2019, May 31, 2020 and May 31, 2021. The first achievement date occurred on October 2, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 50,000 units vesting, as reflected on Table I, and 100,000 units remaining subject to performance-based and time-based vesting conditions.

F2 · derivative.exercise_date: Grant of 150,000 Performance-Based Restricted Stock Units, each of which represents a contingent right to receive one share of common stock of QMCO, with vesting subject to the achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022. Vesting is subject to continued employment with the Company through the later of the achievement date or service vesting date, which occurs in three equal annual installments on May 31, 2019, May 31, 2020 and May 31, 2021. The first achievement date occurred on October 2, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 50,000 units vesting, as reflected on Table I, and 100,000 units remaining subject to performance-based and time-based vesting conditions.

SEC source: 0000899243-19-025105 · doc4.xml · nonDerivative · entry 2

King Elizabeth · CIK 0001770712 · Chief Revenue Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 200,000

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.

F2 · security: Grant of 150,000 Performance-Based Restricted Stock Units, each of which represents a contingent right to receive one share of common stock of QMCO, with vesting subject to the achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022. Vesting is subject to continued employment with the Company through the later of the achievement date or service vesting date, which occurs in three equal annual installments on May 31, 2019, May 31, 2020 and May 31, 2021. The first achievement date occurred on October 2, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 50,000 units vesting, as reflected on Table I, and 100,000 units remaining subject to performance-based and time-based vesting conditions.

SEC source: 0000899243-19-025105 · doc4.xml · nonDerivative · entry 1

King Elizabeth · CIK 0001770712 · Chief Revenue Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 150,000

F1 · security: Grant of Restricted Stock Units ("RSUs"), each of which represents a contingent right to receive one share of common stock of QMCO. The RSUs vest in three equal annual installments on April 1, 2020, April 1, 2021 and April 1, 2022, subject to continued employment.

SEC source: 0000899243-19-025103 · doc4.xml · derivative · entry 2

DODSON J MICHAEL · CIK 0001231559 · See Remarks

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 83,333

Underlying: Common Stock · 41,667 shares

Expires 2029-10-02

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 · derivative.exercise_price: Performance-Based Restricted Stock Units that were previously reported on August 27, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The first achievement date occurred on October 2, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 41,667 units vesting, as reflected on Table I, and 83,333 units remaining subject to performance-based and time-based vesting conditions.

F1 · derivative.exercise_date: Performance-Based Restricted Stock Units that were previously reported on August 27, 2019, which vest in three equal components upon the later of achievement of specified levels of the average closing prices of a share of QMCO common stock during any sixty (60) day trading period between June 1, 2018 and May 31, 2022, and upon specified service dates, whichever is later. The first achievement date occurred on October 2, 2019, as certified by the leadership and compensation committee of QMCO, resulting in 41,667 units vesting, as reflected on Table I, and 83,333 units remaining subject to performance-based and time-based vesting conditions.