Seagate Technology — Director's Dealing 2011

Apr 5, 2011

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Seagate Technology plc (STX)
CIK: 0001137789
Period of Report: 2011-04-01

Reporting Person: MOSLEY WILLIAM D (EVP, Operations)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2011-04-01	Ordinary Shares	M	19286	$13.62	Acquired	35390.5977	Direct
2011-04-01	Ordinary Shares	S	19286	$15.00	Disposed	16104.5977	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2011-04-01	NQ Stock Option	$13.62	M	19286	Disposed	2011-09-16	Ordinary Shares (19286)	Direct

Footnotes

F1: Includes 682 shares purchased on January 31, 2011 under the Employee Stock Purchase Plan at $10.9905 per share.

F2: Excludes 61,120 Performance Unit Shares and 22,000 Performance Shares previously reported on Mr. Mosley's Form 4 dated September 15, 2010. The vesting of of these awards remain subject to the achievement of performance goals that are not tied to the market price of the Company's ordinary shares. Pursuant to the Securities and Exchange Commission's interpretative guidance, these Performance Unit Shares and Performance Shares are not required to be reported on Mr. Mosley's Section 16 filings until such performance goals have been achieved.

F3: The Sale reported on this Form 4 was affected by a 10b5-1 trading plan adopted by the Reporting Person on February 22, 2011.

F4: Options granted to the Reporting Person under the 2001 Share Option Plan and are subject to a five-year vesting schedule. One quarter of the shares vested as of September 16, 2005. The remainder of the shares vested proportionally eache month over the 48 months following September 16, 2005.