Edgar Filing: MOSLEY WILLIAM D

Ownership Submission

FORM 4

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
STATEMENT OF CHANGES IN 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 ^*

MOSLEY WILLIAM D

2. Issuer Name and Ticker or Trading Symbol
Seagate Technology plc [STX]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

_____ Director	_____ 10% Owner
__X__ Officer (give title below)	_____ Other (specify below)
EVP, Operations

(Last)

(First)

(Middle)

SEAGATE TECHNOLOGY PLC, 10200 S. DE ANZA BOULEVARD

3. Date of Earliest Transaction (Month/Day/Year)
02/01/2012

(Street)

CUPERTINO, CA 95014

4. If Amendment, Date Original Filed(Month/Day/Year)

6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person

(City)

(State)

(Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
1.Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Ordinary Shares	02/01/2012		M		16,302	A	$ 11.065	30,592.5977	D
Ordinary Shares	02/01/2012		M		83,698	A	$ 4.045	114,290.5977	D
Ordinary Shares	02/01/2012		S		16,302	D	$ 23.7052 ⁽¹⁾	97,988.5977	D
Ordinary Shares	02/01/2012		S		83,698	D	$ 23.7179 ⁽¹⁾	14,290.5977	D

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
	Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.		SEC 1474 (9-02)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security
(Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code
(Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date
(Month/Day/Year)

7. Title and Amount of Underlying Securities
(Instr. 3 and 4)

8. Price of Derivative Security
(Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)

11. Nature of Indirect Beneficial Ownership
(Instr. 4)

Code

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

NQ Stock Options

$ 11.065

02/01/2012

16,302

09/13/2010⁽²⁾

09/13/2016

Ordinary Shares

16,302

$ 0

121,198

NQ Stock Options

$ 4.045

02/01/2012

83,698

01/30/2010⁽³⁾

01/30/2016

Ordinary Shares

83,698

$ 0

387,136

Reporting Owners

Reporting Owner Name / Address	Relationships
Reporting Owner Name / Address	Director	10% Owner	Officer	Other
MOSLEY WILLIAM D SEAGATE TECHNOLOGY PLC 10200 S. DE ANZA BOULEVARD CUPERTINO, CA 95014			EVP, Operations

Signatures

/S/ Roberta S Cohen for William D Mosley		02/03/2012
^**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(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)	Shares were sold under a 10b5-1 trading plan adopted by the Reporting Person on January 13, 2012.
(2)	Options granted the Reporting Person under the Issuer's 2004 Stock Compensation Plan are subject to a four-year vesting schedule. One quarter of the option shares vested on September 13, 2010. The remaining shares are vesting and will continue to vest proportionally each month over the 36 months following September 13, 2010.
(3)	Options granted the Reporting Person under the Issuer's 2004 Stock Compensation Plan are subject to a four-year vesting schedule. One quarter of the option shares vested on January 30, 2010. The remaining shares are vesting and will continue to vest proportionally each month over the 36 months following January 30, 2010

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