STX

SEC source: 0001137789-18-000036 · wf-form4_152848901401756.xml · nonDerivative · entry 1

LUCZO STEPHEN J · CIK 0001248260 · Director · Executive Chairman & COB

10b5-1 filing: Not disclosed

Ownership: Indirect · Stephen J Luczo Revocable Trust dated January 26, 2001

Disclosed balance after: 868,416

F1 · price: On May 22, 2018, the Reporting Person gifted 10,000 Ordinary Shares from the Stephen J. Luczo Revocable Trust dated January 26, 2001.

SEC source: 0001137789-18-000033 · wf-form4_152694403745107.xml · nonDerivative · entry 1

LUCZO STEPHEN J · CIK 0001248260 · Director · Executive Chairman & COB

10b5-1 filing: Not disclosed

Ownership: Indirect · Stephen J Luczo Revocable Trust dated January 26, 2001

Disclosed balance after: 878,416

F1 · shares: Ordinary Shares sold under a 10b5-1 trading plan adopted by the Reporting Person.

SEC source: 0001137789-18-000031 · wf-form4_152651263277311.xml · derivative · entry 4

Nygaard Jeffrey D. · CIK 0001720273 · Executive Vice President

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Ordinary Shares · 2,188 shares

Expires 2019-09-10

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_date: Options granted to the Reporting Person under the Seagate Technology plc 2012 Equity Incentive Plan (the "Plan") are subject to a four-year vesting schedule. One quarter of the options vested on September 10, 2013. The remaining options vested in equal monthly installments over the 36 months following September 10, 2013.

SEC source: 0001137789-18-000031 · wf-form4_152651263277311.xml · nonDerivative · entry 2

Nygaard Jeffrey D. · CIK 0001720273 · Executive Vice President

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

SEC source: 0001137789-18-000031 · wf-form4_152651263277311.xml · nonDerivative · entry 1

Nygaard Jeffrey D. · CIK 0001720273 · Executive Vice President

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,188

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 · balance_after: Includes 479 Ordinary Shares purchased by Reporting Person on January 31, 2018 under the Issuer's Employee Stock Purchase Plan. Such acquisition is exempt from reporting pursuant to Rule 16b-3 under the Securities Exchange Act of 1934.

SEC source: 0001137789-18-000029 · wf-form4_152607645626634.xml · nonDerivative · entry 3

ZANDER EDWARD J · CIK 0001251587 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · The Edward and Mona Zander Trust dtd 4/19/93

Disclosed balance after: 37,615

F2 · shares: On May 8, 2018, the Reporting Person gifted 14,000 Ordinary Shares from The Edward and Mona Zander Trust dtd April 19, 1993 to the Mona and Edward Zander Family Foundation, which is under the beneficial ownership of the Reporting Person to the extent of his pecuniary interest therein. The subsequent sale of the 14,000 ordinary shares on May 9, 2018 from the Mona and Edward Zander Family Foundation is being reported as an open-market sale.

SEC source: 0001137789-18-000029 · wf-form4_152607645626634.xml · nonDerivative · entry 1

ZANDER EDWARD J · CIK 0001251587 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · Zanadu Capital Partners, L.P.

Disclosed balance after: 16,698

F1 · ownership.nature: These shares are held by Zanadu Capital Partners, L.P. (the "Partnership"), and the number reported reflects the aggregate number of shares held by the Partnership. The Reporting Person is a general partner of the Partnership. The reporting person disclaims beneficial ownership in the shares held by the Partnership except to the extent of his pecuniary interest therein.

SEC source: 0001418812-18-000044 · primary_doc.xml · derivative · entry 3

ValueAct Holdings, L.P. · CIK 0001418814 · Director · See Remarks

ValueAct Capital Master Fund, L.P. · CIK 0001464912 · Director · See Remarks

VA Partners I, LLC · CIK 0001418812 · Director · See Remarks

ValueAct Capital Management, L.P. · CIK 0001351069 · Director · See Remarks

ValueAct Capital Management, LLC · CIK 0001351073 · Director · See Remarks

ValueAct Holdings GP, LLC · CIK 0001418813 · Director · See Remarks

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 946,100

Underlying: Ordinary Shares · 112,556 shares

Expires 2018-12-03

F4 · derivative.exercise_price: On May 8, 2018, ValueAct Capital Master Fund, L.P. entered into forward contracts obligating ValueAct Capital Master Fund, L.P. to purchase 112,556 shares at $55.93 subject to conditions that become satisfied on June 2, 2018.

F4 · price: On May 8, 2018, ValueAct Capital Master Fund, L.P. entered into forward contracts obligating ValueAct Capital Master Fund, L.P. to purchase 112,556 shares at $55.93 subject to conditions that become satisfied on June 2, 2018.

F1 · ownership.nature: Each reporting person listed herein disclaims beneficial ownership of the reported securities except to the extent of its pecuniary interest therein, and this report shall not be deemed an admission that such person is the beneficial owner of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

F2 · ownership.nature: The securities reported herein are held by ValueAct Capital Master Fund, L.P. and may be deemed to be indirectly beneficially owned by (i) VA Partners I, LLC as General Partner of ValueAct Capital Master Fund, L.P., (ii) ValueAct Capital Management, L.P. as the manager of ValueAct Capital Master Fund, L.P., (iii) ValueAct Capital Management, LLC as General Partner of ValueAct Capital Management, L.P., (iv) ValueAct Holdings, L.P. as the sole owner of the limited partnership interests of ValueAct Capital Management, L.P. and the membership interests of ValueAct Capital Management, LLC and as the majority owner of the membership interests of VA Partners I, LLC and (v) ValueAct Holdings GP, LLC as General Partner of ValueAct Holdings, L.P.

SEC source: 0001137789-18-000029 · wf-form4_152607645626634.xml · nonDerivative · entry 2

ZANDER EDWARD J · CIK 0001251587 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · The Edward and Mona Zander Trust dtd 4/19/93

Disclosed balance after: 37,615

F2 · shares: On May 8, 2018, the Reporting Person gifted 14,000 Ordinary Shares from The Edward and Mona Zander Trust dtd April 19, 1993 to the Mona and Edward Zander Family Foundation, which is under the beneficial ownership of the Reporting Person to the extent of his pecuniary interest therein. The subsequent sale of the 14,000 ordinary shares on May 9, 2018 from the Mona and Edward Zander Family Foundation is being reported as an open-market sale.

SEC source: 0001137789-18-000027 · wf-form4_152606125334430.xml · nonDerivative · entry 1

LUCZO STEPHEN J · CIK 0001248260 · Director · Executive Chairman & COB

10b5-1 filing: Not disclosed

Ownership: Indirect · Stephen J Luczo Revocable Trust dated January 26, 2001

Disclosed balance after: 884,097

F1 · price: These Ordinary Shares were sold in multiple transactions at sales prices ranging from $55.91 to $56.13, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, 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 range set forth in the footnote of this Form 4.

SEC source: 0001418812-18-000044 · primary_doc.xml · derivative · entry 2

ValueAct Holdings, L.P. · CIK 0001418814 · Director · See Remarks

ValueAct Capital Master Fund, L.P. · CIK 0001464912 · Director · See Remarks

VA Partners I, LLC · CIK 0001418812 · Director · See Remarks

ValueAct Capital Management, L.P. · CIK 0001351069 · Director · See Remarks

ValueAct Capital Management, LLC · CIK 0001351073 · Director · See Remarks

ValueAct Holdings GP, LLC · CIK 0001418813 · Director · See Remarks

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 833,544

Underlying: Ordinary Shares · 61,098 shares

Expires 2018-12-03

F3 · derivative.exercise_price: On May 7, 2018, ValueAct Capital Master Fund, L.P. entered into forward contracts obligating ValueAct Capital Master Fund, L.P. to purchase 61,098 shares at $55.89 subject to conditions that become satisfied on June 2, 2018.

F3 · price: On May 7, 2018, ValueAct Capital Master Fund, L.P. entered into forward contracts obligating ValueAct Capital Master Fund, L.P. to purchase 61,098 shares at $55.89 subject to conditions that become satisfied on June 2, 2018.

F1 · ownership.nature: Each reporting person listed herein disclaims beneficial ownership of the reported securities except to the extent of its pecuniary interest therein, and this report shall not be deemed an admission that such person is the beneficial owner of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

F2 · ownership.nature: The securities reported herein are held by ValueAct Capital Master Fund, L.P. and may be deemed to be indirectly beneficially owned by (i) VA Partners I, LLC as General Partner of ValueAct Capital Master Fund, L.P., (ii) ValueAct Capital Management, L.P. as the manager of ValueAct Capital Master Fund, L.P., (iii) ValueAct Capital Management, LLC as General Partner of ValueAct Capital Management, L.P., (iv) ValueAct Holdings, L.P. as the sole owner of the limited partnership interests of ValueAct Capital Management, L.P. and the membership interests of ValueAct Capital Management, LLC and as the majority owner of the membership interests of VA Partners I, LLC and (v) ValueAct Holdings GP, LLC as General Partner of ValueAct Holdings, L.P.

SEC source: 0001418812-18-000040 · primary_doc.xml · derivative · entry 4

ValueAct Holdings, L.P. · CIK 0001418814 · Director · See Remarks

ValueAct Capital Master Fund, L.P. · CIK 0001464912 · Director · See Remarks

VA Partners I, LLC · CIK 0001418812 · Director · See Remarks

ValueAct Capital Management, L.P. · CIK 0001351069 · Director · See Remarks

ValueAct Capital Management, LLC · CIK 0001351073 · Director · See Remarks

ValueAct Holdings GP, LLC · CIK 0001418813 · Director · See Remarks

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 772,446

Underlying: Ordinary Shares · 61,463 shares

Expires 2018-11-05

F5 · derivative.exercise_price: On May 4, 2018, ValueAct Capital Master Fund, L.P. entered into forward contracts obligating ValueAct Capital Master Fund, L.P. to purchase 61,463 shares at $54.91 subject to conditions that become satisfied on June 2, 2018.

F5 · price: On May 4, 2018, ValueAct Capital Master Fund, L.P. entered into forward contracts obligating ValueAct Capital Master Fund, L.P. to purchase 61,463 shares at $54.91 subject to conditions that become satisfied on June 2, 2018.

F1 · ownership.nature: Each reporting person listed herein disclaims beneficial ownership of the reported securities except to the extent of its pecuniary interest therein, and this report shall not be deemed an admission that such person is the beneficial owner of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

F2 · ownership.nature: The securities reported herein are held by ValueAct Capital Master Fund, L.P. and may be deemed to be indirectly beneficially owned by (i) VA Partners I, LLC as General Partner of ValueAct Capital Master Fund, L.P., (ii) ValueAct Capital Management, L.P. as the manager of ValueAct Capital Master Fund, L.P., (iii) ValueAct Capital Management, LLC as General Partner of ValueAct Capital Management, L.P., (iv) ValueAct Holdings, L.P. as the sole owner of the limited partnership interests of ValueAct Capital Management, L.P. and the membership interests of ValueAct Capital Management, LLC and as the majority owner of the membership interests of VA Partners I, LLC and (v) ValueAct Holdings GP, LLC as General Partner of ValueAct Holdings, L.P.

SEC source: 0001418812-18-000040 · primary_doc.xml · derivative · entry 3

ValueAct Holdings, L.P. · CIK 0001418814 · Director · See Remarks

ValueAct Capital Master Fund, L.P. · CIK 0001464912 · Director · See Remarks

VA Partners I, LLC · CIK 0001418812 · Director · See Remarks

ValueAct Capital Management, L.P. · CIK 0001351069 · Director · See Remarks

ValueAct Capital Management, LLC · CIK 0001351073 · Director · See Remarks

ValueAct Holdings GP, LLC · CIK 0001418813 · Director · See Remarks

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 710,983

Underlying: Ordinary Shares · 449,048 shares

Expires 2018-11-04

F4 · derivative.exercise_price: On May 3, 2018, ValueAct Capital Master Fund, L.P. entered into forward contracts obligating ValueAct Capital Master Fund, L.P. to purchase 449,048 shares at $54.72 subject to conditions that become satisfied on June 2, 2018.

F4 · price: On May 3, 2018, ValueAct Capital Master Fund, L.P. entered into forward contracts obligating ValueAct Capital Master Fund, L.P. to purchase 449,048 shares at $54.72 subject to conditions that become satisfied on June 2, 2018.

F1 · ownership.nature: Each reporting person listed herein disclaims beneficial ownership of the reported securities except to the extent of its pecuniary interest therein, and this report shall not be deemed an admission that such person is the beneficial owner of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

F2 · ownership.nature: The securities reported herein are held by ValueAct Capital Master Fund, L.P. and may be deemed to be indirectly beneficially owned by (i) VA Partners I, LLC as General Partner of ValueAct Capital Master Fund, L.P., (ii) ValueAct Capital Management, L.P. as the manager of ValueAct Capital Master Fund, L.P., (iii) ValueAct Capital Management, LLC as General Partner of ValueAct Capital Management, L.P., (iv) ValueAct Holdings, L.P. as the sole owner of the limited partnership interests of ValueAct Capital Management, L.P. and the membership interests of ValueAct Capital Management, LLC and as the majority owner of the membership interests of VA Partners I, LLC and (v) ValueAct Holdings GP, LLC as General Partner of ValueAct Holdings, L.P.

SEC source: 0001418812-18-000040 · primary_doc.xml · derivative · entry 2

ValueAct Holdings, L.P. · CIK 0001418814 · Director · See Remarks

ValueAct Capital Master Fund, L.P. · CIK 0001464912 · Director · See Remarks

VA Partners I, LLC · CIK 0001418812 · Director · See Remarks

ValueAct Capital Management, L.P. · CIK 0001351069 · Director · See Remarks

ValueAct Capital Management, LLC · CIK 0001351073 · Director · See Remarks

ValueAct Holdings GP, LLC · CIK 0001418813 · Director · See Remarks

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 261,935

Underlying: Ordinary Shares · 261,935 shares

Expires 2018-11-03

F3 · derivative.exercise_price: On May 2, 2018, ValueAct Capital Master Fund, L.P. entered into forward contracts obligating ValueAct Capital Master Fund, L.P. to purchase 261,935 shares at $53.15 subject to conditions that become satisfied on June 2, 2018.

F3 · price: On May 2, 2018, ValueAct Capital Master Fund, L.P. entered into forward contracts obligating ValueAct Capital Master Fund, L.P. to purchase 261,935 shares at $53.15 subject to conditions that become satisfied on June 2, 2018.

F1 · ownership.nature: Each reporting person listed herein disclaims beneficial ownership of the reported securities except to the extent of its pecuniary interest therein, and this report shall not be deemed an admission that such person is the beneficial owner of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

F2 · ownership.nature: The securities reported herein are held by ValueAct Capital Master Fund, L.P. and may be deemed to be indirectly beneficially owned by (i) VA Partners I, LLC as General Partner of ValueAct Capital Master Fund, L.P., (ii) ValueAct Capital Management, L.P. as the manager of ValueAct Capital Master Fund, L.P., (iii) ValueAct Capital Management, LLC as General Partner of ValueAct Capital Management, L.P., (iv) ValueAct Holdings, L.P. as the sole owner of the limited partnership interests of ValueAct Capital Management, L.P. and the membership interests of ValueAct Capital Management, LLC and as the majority owner of the membership interests of VA Partners I, LLC and (v) ValueAct Holdings GP, LLC as General Partner of ValueAct Holdings, L.P.

SEC source: 0001137789-18-000025 · wf-form4_152356681422211.xml · nonDerivative · entry 1

LUCZO STEPHEN J · CIK 0001248260 · Director · Executive Chairman & COB

10b5-1 filing: Not disclosed

Ownership: Indirect · Stephen J Luczo Revocable Trust dated January 26, 2001

Disclosed balance after: 984,097

F1 · kind: These Ordinary Shares are being sold under a 10b5-1 Trading Plan adopted by the Reporting Person.

SEC source: 0001137789-18-000024 · wf-form4_152287307106022.xml · nonDerivative · entry 1

LUCZO STEPHEN J · CIK 0001248260 · Director · Executive Chairman & COB

10b5-1 filing: Not disclosed

Ownership: Indirect · Stephen J Luczo Revocable Trust dated January 26, 2001

Disclosed balance after: 988,717

F1 · price: These Ordinary Shares were sold in multiple transactions at sales prices ranging from $60.00 to $60.05, inclusive, under a 10b5-1 Trading Plan adopted by the Reporting Person. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, 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 range set forth in the footnote of this Form 4.

F2 · balance_after: On February 14, 2018, the Reporting Person transferred 72,484 Ordinary Shares, previously held directly, to the Stephen J. Luczo Revocable Trust dated January 26, 2001.

SEC source: 0001137789-18-000022 · wf-form4_152045799874698.xml · derivative · entry 9

MORTON DAVID H JR · CIK 0001476070 · EVP & CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 96,013

Underlying: Ordinary Shares · 12,389 shares

Expires 2023-09-09

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 · derivative.exercise_date: Options granted to the Reporting Person under the Seagate Technology plc 2012 Equity Incentive Plan are subject to a four-year vesting schedule. Subject to continuous employment, one quarter of the option shares vested on September 9, 2017. The remaining options shares vest in equal monthly installments over the 36 months following September 9, 2017.

SEC source: 0001137789-18-000022 · wf-form4_152045799874698.xml · derivative · entry 8

MORTON DAVID H JR · CIK 0001476070 · EVP & CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 10,125

Underlying: Ordinary Shares · 15,452 shares

Expires 2022-09-09

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 · derivative.exercise_date: Options granted to the Reporting Person under the Seagate Technology plc 2012 Equity Incentive Plan are subject to a four-year vesting schedule. Subject to continuous employment, one quarter of the option shares vested on September 9, 2016. The remaining option shares vest in equal monthly installments over the 36 months following September 9, 2016.

SEC source: 0001137789-18-000022 · wf-form4_152045799874698.xml · derivative · entry 7

MORTON DAVID H JR · CIK 0001476070 · EVP & CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Ordinary Shares · 4,894 shares

Expires 2020-09-09

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 · derivative.exercise_date: Options granted to the Reporting Person under the Seagate Technology plc 2012 Equity Incentive Plan are subject to a four-year vesting schedule. Subject to continuous employment, one quarter of the option shares vested on September 9, 2014. The remaining option shares vest in equal monthly installments over the 36 months following September 9, 2014.

SEC source: 0001137789-18-000022 · wf-form4_152045799874698.xml · derivative · entry 6

MORTON DAVID H JR · CIK 0001476070 · EVP & CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Ordinary Shares · 2,407 shares

Expires 2019-09-10

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_date: Options granted to the Reporting Person under the Seagate Technology plc 2012 Equity Incentive Plan are subject to a four-year vesting schedule. Subject to continuous employment, one quarter of the option shares vested on September 10, 2013. The remaining option shares vest in equal monthly installments over the 36 months following September 10, 2013.

SEC source: 0001137789-18-000022 · wf-form4_152045799874698.xml · nonDerivative · entry 5

MORTON DAVID H JR · CIK 0001476070 · EVP & CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 6,133

F1 · price: These Ordinary Shares were sold in multiple transactions at sales prices ranging from $55.00 to $55.01, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, 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 range set forth in the footnote of this Form 4.

SEC source: 0001137789-18-000022 · wf-form4_152045799874698.xml · nonDerivative · entry 4

MORTON DAVID H JR · CIK 0001476070 · EVP & CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 41,275

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.

SEC source: 0001137789-18-000022 · wf-form4_152045799874698.xml · nonDerivative · entry 3

MORTON DAVID H JR · CIK 0001476070 · EVP & CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 28,886

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.

SEC source: 0001137789-18-000022 · wf-form4_152045799874698.xml · nonDerivative · entry 2

MORTON DAVID H JR · CIK 0001476070 · EVP & CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 13,434

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.

SEC source: 0001137789-18-000022 · wf-form4_152045799874698.xml · nonDerivative · entry 1

MORTON DAVID H JR · CIK 0001476070 · EVP & CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,540

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.

SEC source: 0001137789-18-000020 · wf-form4_151977463079914.xml · nonDerivative · entry 1

Geldmacher Jay L · CIK 0001462488 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 4,240

SEC source: 0001137789-18-000019 · wf-form4_151934112596461.xml · nonDerivative · entry 2

MORTON DAVID H JR · CIK 0001476070 · EVP & CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 6,133

F3 · shares: Ordinary Shares sold under 10b5-1 Trading Plan adopted by the Reporting Person on November 14, 2017.

F4 · price: These Ordinary Shares were sold in multiple transactions at sales prices ranging from $51.46 to $52.14, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, 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 range set forth in the footnote of this Form 4.

SEC source: 0001137789-18-000019 · wf-form4_151934112596461.xml · nonDerivative · entry 1

MORTON DAVID H JR · CIK 0001476070 · EVP & CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 17,624

F1 · shares: These Ordinary Shares are withheld securities to cover tax liabilities incident to the vesting of securities previously reported on one or more Forms 4 by the Reporting Person in accordance with Rule 16b-3.

F2 · balance_after: Includes 572 Ordinary Shares purchased by Reporting Person on January 31, 2018 under the Issuer's Employee Stock Purchase Plan. Such acquisition is exempt from reporting pursuant to Rule 16b-3 under the Securities Exchange Act of 1934.

SEC source: 0001137789-18-000017 · wf-form4_151753345818461.xml · derivative · entry 9

LUCZO STEPHEN J · CIK 0001248260 · Director · Executive Chairman & COB

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Ordinary Shares · 107,922 shares

Expires 2019-08-01

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.

F9 · derivative.exercise_date: Options granted to the Reporting Person under the Seagate Technology plc 2012 Equity Incentive Plan are subject to a four-year vesting schedule. Subject to continuous employment, one quarter of the options vested August 1, 2013. The remaining options vest in equal monthly installments over the 36 months following August 1, 2013.

SEC source: 0001137789-18-000017 · wf-form4_151753345818461.xml · derivative · entry 8

LUCZO STEPHEN J · CIK 0001248260 · Director · Executive Chairman & COB

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Ordinary Shares · 206,300 shares

Expires 2019-08-01

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.

F8 · derivative.exercise_date: Options granted to the Reporting Person under the Seagate Technology plc 2012 Equity Incentive Plan (the "Plan") are subject to a four-year vesting schedule. Subject to continuous employment, one quarter of the options vested August 1, 2013. The remaining options vest in equal monthly installments over the 36 months following August 1, 2013.

SEC source: 0001137789-18-000017 · wf-form4_151753345818461.xml · nonDerivative · entry 5

LUCZO STEPHEN J · CIK 0001248260 · Director · Executive Chairman & COB

10b5-1 filing: Not disclosed

Ownership: Indirect · Stephen J Luczo Revocable Trust dated January 26, 2001

Disclosed balance after: 921,613

F7 · price: These Ordinary Shares were sold in multiple transactions at sales prices ranging from $55.48 to $55.65, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, 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 range set forth in the footnote of this Form 4.

SEC source: 0001137789-18-000018 · wf-form4_151753360586338.xml · derivative · entry 4

MURPHY JAMES J · CIK 0001234677 · EVP, Sales & Marketing

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 386,773

Underlying: Ordinary Shares · 12,001 shares

Expires 2023-12-20

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.

SEC source: 0001137789-18-000018 · wf-form4_151753360586338.xml · nonDerivative · entry 3

MURPHY JAMES J · CIK 0001234677 · EVP, Sales & Marketing

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 10,815

F1 · balance_after: Includes 405 Ordinary Shares purchased by Reporting Person on January 31, 2018 under the Issuer's Employee Stock Purchase Plan. Such acquisition is exempt from reporting pursuant to Rule 16b-3 under the Securities Exchange Act of 1934.

SEC source: 0001137789-18-000018 · wf-form4_151753360586338.xml · nonDerivative · entry 2

MURPHY JAMES J · CIK 0001234677 · EVP, Sales & Marketing

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 12,584

SEC source: 0001137789-18-000018 · wf-form4_151753360586338.xml · nonDerivative · entry 1

MURPHY JAMES J · CIK 0001234677 · EVP, Sales & Marketing

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 24,585

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.

SEC source: 0001137789-18-000017 · wf-form4_151753345818461.xml · nonDerivative · entry 4

LUCZO STEPHEN J · CIK 0001248260 · Director · Executive Chairman & COB

10b5-1 filing: Not disclosed

Ownership: Indirect · Stephen J Luczo Revocable Trust dated January 26, 2001

Disclosed balance after: 1,021,613

F2 · balance_after: On September 13, 2017 the Reporting Person transferred 34,375 shares held directly to the Stephen J. Luczo Revocable Trust dated January 26, 2001.

F3 · balance_after: On September 27, 2017 the Reporting Person transferred 33,857 shares held directly to the Stephen J. Luczo Revocable Trust dated January 26, 2001.

F5 · balance_after: Includes 635 shares acquired on October 5, 2017 and on January 4, 2018 under the Seagate Technology plc's Dividend Reinvestment Program.

F6 · balance_after: On January 30, 2018 the Reporting Person transferred 118,588 shares from the Stephen J. Luczo 2016 Grantor Retained Annuity Trust to Stephen J. Luczo Revocable Trust dated January 26, 2001.

SEC source: 0001137789-18-000017 · wf-form4_151753345818461.xml · nonDerivative · entry 3

LUCZO STEPHEN J · CIK 0001248260 · Director · Executive Chairman & COB

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 72,484

F4 · price: These Ordinary Shares were sold in multiple transactions at sales prices ranging from $54.46 to $55.00, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, 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 range set forth in the footnote of this Form 4.

SEC source: 0001137789-18-000017 · wf-form4_151753345818461.xml · nonDerivative · entry 2

LUCZO STEPHEN J · CIK 0001248260 · Director · Executive Chairman & COB

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 314,222

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.

SEC source: 0001137789-18-000017 · wf-form4_151753345818461.xml · nonDerivative · entry 1

LUCZO STEPHEN J · CIK 0001248260 · Director · Executive Chairman & COB

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 206,300

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 · balance_after: On November 4, 2016, the Reporting Person transferred 27,188 Ordinary Shares, previously held directly, to the Stephen J. Luczo Revocable Trust dated January 26, 2001. These 27,188 shares were inadvertently reported as directly held by the Reporting Person on subsequent Form 4's filed on April 27, 2017 and thereafter.

F2 · balance_after: On September 13, 2017 the Reporting Person transferred 34,375 shares held directly to the Stephen J. Luczo Revocable Trust dated January 26, 2001.

F3 · balance_after: On September 27, 2017 the Reporting Person transferred 33,857 shares held directly to the Stephen J. Luczo Revocable Trust dated January 26, 2001.

SEC source: 0001137789-18-000016 · wf-form4_151753270266325.xml · nonDerivative · entry 2

PARK CHONG SUP · CIK 0001216771 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · Park Family Trust

Disclosed balance after: 18,632

F2 · price: These Ordinary Shares were sold in multiple transactions at sales prices ranging from $54.22 to $54.24, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, 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 range set forth in the footnote of this Form 4.

SEC source: 0001418812-18-000008 · primary_doc.xml · derivative · entry 2

Haggart Dylan G. · CIK 0001684185 · Director · See Remarks

ValueAct Holdings, L.P. · CIK 0001418814 · Director · See Remarks

ValueAct Capital Master Fund, L.P. · CIK 0001464912 · Director · See Remarks

VA Partners I, LLC · CIK 0001418812 · Director · See Remarks

ValueAct Capital Management, L.P. · CIK 0001351069 · Director · See Remarks

ValueAct Capital Management, LLC · CIK 0001351073 · Director · See Remarks

ValueAct Holdings GP, LLC · CIK 0001418813 · Director · See Remarks

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,285

Underlying: Ordinary Shares · 5,285 shares

Expires not disclosed

F3 · derivative.exercise_price: Consists of a grant of restricted share units awarded to Mr. Haggart under the Amended and Restated Seagate Technology plc 2012 Equity Incentive Plan for no consideration. Each restricted share unit represents a contingent right to receive one Ordinary Share of the Issuer. Subject to Mr. Haggart's continuous service with the Issuer, shares will be released to Mr. Haggart on the earlier of (i) one year from the date of grant and (ii) one day prior to the next annual general meeting of the shareholders of the Issuer following the end of the fiscal year ending on June 29, 2018.

F3 · price: Consists of a grant of restricted share units awarded to Mr. Haggart under the Amended and Restated Seagate Technology plc 2012 Equity Incentive Plan for no consideration. Each restricted share unit represents a contingent right to receive one Ordinary Share of the Issuer. Subject to Mr. Haggart's continuous service with the Issuer, shares will be released to Mr. Haggart on the earlier of (i) one year from the date of grant and (ii) one day prior to the next annual general meeting of the shareholders of the Issuer following the end of the fiscal year ending on June 29, 2018.

F3 · derivative.exercise_date: Consists of a grant of restricted share units awarded to Mr. Haggart under the Amended and Restated Seagate Technology plc 2012 Equity Incentive Plan for no consideration. Each restricted share unit represents a contingent right to receive one Ordinary Share of the Issuer. Subject to Mr. Haggart's continuous service with the Issuer, shares will be released to Mr. Haggart on the earlier of (i) one year from the date of grant and (ii) one day prior to the next annual general meeting of the shareholders of the Issuer following the end of the fiscal year ending on June 29, 2018.

F3 · derivative.expiration_date: Consists of a grant of restricted share units awarded to Mr. Haggart under the Amended and Restated Seagate Technology plc 2012 Equity Incentive Plan for no consideration. Each restricted share unit represents a contingent right to receive one Ordinary Share of the Issuer. Subject to Mr. Haggart's continuous service with the Issuer, shares will be released to Mr. Haggart on the earlier of (i) one year from the date of grant and (ii) one day prior to the next annual general meeting of the shareholders of the Issuer following the end of the fiscal year ending on June 29, 2018.

F2 · ownership.direct: Each reporting person listed herein disclaims beneficial ownership of the reported securities except to the extent of its pecuniary interest therein, and this report shall not be deemed an admission that such person is the beneficial owner of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

F4 · ownership.direct: The ValueAct entities referred to in this footnote 4 are collectively referred to herein as "ValueAct Capital." Under an agreement with ValueAct Capital, Dylan G. Haggart is deemed to hold the restricted share units for the benefit of the limited partners of ValueAct Capital Master Fund, L.P. and indirectly for (i) VA Partners I, LLC as General Partner of ValueAct Capital Master Fund, L.P., (ii) ValueAct Capital Management, L.P. as the manager of ValueAct Capital Master Fund, L.P., (iii) ValueAct Capital Management, LLC as General Partner of ValueAct Capital Management, L.P., (iv) ValueAct Holdings, L.P. as the sole owner of the limited partnership interests of ValueAct Capital Management, L.P. and the membership interests of ValueAct Capital Management, LLC and as the majority owner of the membership interests of VA Partners I, LLC and (v) ValueAct Holdings GP, LLC as General Partner of ValueAct Holdings, L.P.

SEC source: 0001137789-18-000013 · wf-form4_151615193203291.xml · nonDerivative · entry 1

BRACE PHILIP G · CIK 0001336507 · Former President, CSSG

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 16,069

SEC source: 0001137789-18-000012 · wf-form4_151563177646840.xml · nonDerivative · entry 2

BRACE PHILIP G · CIK 0001336507 · Former President, CSSG

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 21,069

F2 · price: These Ordinary Shares were sold in multiple transactions at sales prices ranging from $46.67 to $46.69, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, 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 range set forth in the footnote of this Form 4.

SEC source: 0001137789-18-000012 · wf-form4_151563177646840.xml · nonDerivative · entry 1

BRACE PHILIP G · CIK 0001336507 · Former President, CSSG

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 27,069

F1 · price: These Ordinary Shares were sold in multiple transactions at sales prices ranging from $46.16 to $46.30, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, 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 range set forth in the footnote of this Form 4.

SEC source: 0001137789-18-000011 · wf-form4_151563170593547.xml · nonDerivative · entry 2

LUCZO STEPHEN J · CIK 0001248260 · Director · Executive Chairman & COB

10b5-1 filing: Not disclosed

Ownership: Indirect · Stephen J Luczo Revocable Trust dated January 26, 2001

Disclosed balance after: 854,158

F2 · kind: These Ordinary Shares are being sold under a 10b5-1 Trading Plan previously adopted by the Reporting Person.

F3 · balance_after: On November 14, 2017 the Reporting Person transferred 250,000 shares from the Stephen J. Luczo Revocable Trust dated January 26, 2001 to the Stephen J. Luczo 2017 Grantor Retained Annuity Trust.

SEC source: 0001137789-18-000010 · wf-form4_151563161075901.xml · derivative · entry 3

MORTON DAVID H JR · CIK 0001476070 · EVP & CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 108,402

Underlying: Ordinary Shares · 40,263 shares

Expires 2023-09-09

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_date: Options granted to the Reporting Person under the Seagate Technology plc 2012 Equity Incentive Plan (the "Plan") are subject to a four year vesting schedule. Subject to continuous employment, one quarter of the options vested on September 9, 2017. The remaining options shares vest in equal monthly installments over the 36 months following September 9, 2017.

SEC source: 0001137789-18-000010 · wf-form4_151563161075901.xml · nonDerivative · entry 2

MORTON DAVID H JR · CIK 0001476070 · EVP & CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 25,561

F1 · kind: These Ordinary Shares are being sold under a 10b5-1 Trading Plan adopted by the Reporting Person.

SEC source: 0001137789-18-000010 · wf-form4_151563161075901.xml · nonDerivative · entry 1

MORTON DAVID H JR · CIK 0001476070 · EVP & CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 65,824

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.

SEC source: 0001137789-17-000102 · wf-form4_151397491672246.xml · nonDerivative · entry 1

MURPHY JAMES J · CIK 0001234677 · EVP, Sales & Marketing

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 12,584

F1 · shares: These Ordinary Shares are withheld securities to cover tax liabilities incident to the vesting of securities previously reported on one or more Forms 4 by the Reporting Person in accordance with Rule 16b-3.

F2 · balance_after: Includes 410 Ordinary Shares purchased by Reporting Person on July 31, 2017 under the Issuer's Employee Stock Purchase Plan. Such acquisition is exempt from reporting pursuant to Rule 16b-3 under the Securities Exchange Act of 1934.

SEC source: 0001137789-17-000098 · wf-form4_151216126308861.xml · nonDerivative · entry 2

ZANDER EDWARD J · CIK 0001251587 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · Zanadu Capital Partners, L.P.

Disclosed balance after: 26,316

F2 · price: These Ordinary Shares were sold in multiple transactions at sales prices ranging from $38.73 to $38.78, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, 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 range set forth in the footnote of this Form 4.