Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  ValueAct Holdings, L.P.
2. Date of Event Requiring Statement (Month/Day/Year)
02/07/2019
3. Issuer Name and Ticker or Trading Symbol
Seagate Technology plc [STX]
(Last)
(First)
(Middle)
ONE LETTERMAN DRIVE, BUILDING D, 4TH FLOOR
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

SAN FRANCISCO, CA 94129
6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Ordinary Shares 27,295,160
I
See Footnotes (1) (2)
Ordinary Shares 2,225,000
I
See Footnotes (1) (3)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
ValueAct Holdings, L.P.
ONE LETTERMAN DRIVE
BUILDING D, 4TH FLOOR
SAN FRANCISCO, CA 94129
    X    
ValueAct Capital Master Fund, L.P.
ONE LETTERMAN DRIVE
BUILDING D, 4TH FLOOR
SAN FRANCISCO, CA 94129
    X    
ValueAct Capital Master Fund B, L.P.
ONE LETTERMAN DRIVE
BUILDING D, FOURTH FLOOR
SAN FRANCISCO, CA 94129
    X    
VA Partners I, LLC
ONE LETTERMAN DRIVE
BUILDING D, 4TH FLOOR
SAN FRANCISCO, CA 94129
    X    
ValueAct Capital Management, L.P.
ONE LETTERMAN DRIVE
BUILDING D, 4TH FLOOR
SAN FRANCISCO, CA 94129
    X    
ValueAct Capital Management, LLC
ONE LETTERMAN DRIVE
BUILDING D, 4TH FLOOR
SAN FRANCISCO, CA 94129
    X    
ValueAct Holdings II, L.P.
ONE LETTERMAN DRIVE
BUILDING D, FOURTH FLOOR
SAN FRANCISCO, CA 94129
    X    
ValueAct Holdings GP, LLC
ONE LETTERMAN DRIVE
BUILDING D, 4TH FLOOR
SAN FRANCISCO, CA 94129
    X    

Signatures

VALUEACT HOLDINGS, L.P., By: VALUEACT HOLDINGS GP, LLC, its General Partner, By: /s/ Bradley E. Singer, Chief Operating Officer 02/08/2019
**Signature of Reporting Person Date

VALUEACT CAPITAL MASTER FUND, L.P., By: VA PARTNERS I, LLC, its General Partner, By: /s/ Bradley E. Singer, Chief Operating Officer 02/08/2019
**Signature of Reporting Person Date

VALUEACT CAPITAL MASTER FUND B, L.P., By: VA PARTNERS I, LLC, its General Partner, By: /s/ Bradley E. Singer, Chief Operating Officer 02/08/2019
**Signature of Reporting Person Date

VA PARTNERS I, LLC, By: /s/ Bradley E. Singer, Chief Operating Officer 02/08/2019
**Signature of Reporting Person Date

VALUEACT CAPITAL MANAGEMENT, L.P., By: VALUEACT CAPITAL MANAGEMENT, LLC, its General Partner, By: /s/ Bradley E. Singer, Chief Operating Officer 02/08/2019
**Signature of Reporting Person Date

VALUEACT CAPITAL MANAGEMENT, LLC, By: /s/ Bradley E. Singer, Chief Operating Officer 02/08/2019
**Signature of Reporting Person Date

VALUEACT HOLDINGS II, L.P., By: VALUEACT HOLDINGS GP, LLC, its General Partner, By: /s/ Bradley E. Singer, Chief Operating Officer 02/08/2019
**Signature of Reporting Person Date

VALUEACT HOLDINGS GP, LLC, By: /s/ Bradley E. Singer, Chief Operating Officer 02/08/2019
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) 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.
(2) 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 majority owner of the membership interests of VA Partners I, LLC, (v) ValueAct Holdings II, L.P. as the sole owner of the membership interests of ValueAct Capital Management, LLC and as the majority owner of the limited partnership interests of ValueAct Capital Management, L.P., and (vi) ValueAct Holdings GP, LLC as General Partner of ValueAct Holdings, L.P. and ValueAct Holdings II, L.P.
(3) The securities reported herein are held by ValueAct Capital Master Fund B, 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 B, L.P., (ii) ValueAct Capital Management, L.P. as the manager of ValueAct Capital Master Fund B, L.P., (iii) ValueAct Capital Management, LLC as General Partner of ValueAct Capital Management, L.P., (iv) ValueAct Holdings, L.P. as the majority owner of the membership interests of VA Partners I, LLC, (v) ValueAct Holdings II, L.P. as the sole owner of the membership interests of ValueAct Capital Management, LLC and as the majority owner of the limited partnership interests of ValueAct Capital Management, L.P., and (vi) ValueAct Holdings GP, LLC as General Partner of ValueAct Holdings, L.P. and ValueAct Holdings II, L.P.

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