Seagate (STX) Insider Sales: Mosley Disposes 20K Shares via 10b5-1

Rhea-AI Filing Summary

Seagate Technology Holdings plc (STX) insider sales by CEO/Director William D. Mosley. The Form 4 reports multiple open-market sales on 09/02/2025 executed under a Rule 10b5-1 trading plan adopted February 20, 2025. The reporting person sold blocks of Ordinary Shares: 700 at a weighted average $164.8021, 342 at $165.6669, 400 at $166.6025, 5,843 at $168.2874, 5,715 at $169.0589 and 7,000 at $170.1923. Following these transactions, the filing shows 478,212 shares, then sequentially lower counts down to 458,912 shares, reflecting the cumulative sales. The Form 4 was signed by an attorney-in-fact on 09/04/2025.

Positive

• Transactions executed under a Rule 10b5-1 plan, indicating planned and pre-authorized trades
• Detailed weighted-average prices and price ranges provided in explanatory footnotes
• Reporting person commits to provide trade-level details upon request, supporting transparency

Negative

• None.

Insights

Corporate Governance Expert

TL;DR: CEO/Director Mosley executed several planned sales under a 10b5-1 plan; transactions are disclosed and routine.

The Form 4 discloses multiple open-market dispositions by William D. Mosley on a single trade date, executed pursuant to a documented Rule 10b5-1 plan adopted on February 20, 2025. The filing provides weighted average prices for each block and the remaining beneficial ownership counts after each sale. From a governance perspective, the presence of a 10b5-1 plan and explicit price ranges in the explanatory footnotes supports the view that these sales were pre-planned and compliant with Section 16 reporting requirements. The disclosure includes commitment to provide detailed trade-level prices and volumes upon request.

Securities Analyst

TL;DR: Material share volumes were sold but fully disclosed; this is a routine insider liquidity event, not an undisclosed corporate development.

The reported disposals total 20,000 shares on 09/02/2025 across six reported blocks with weighted average prices between $164.80 and $170.19, reducing beneficial holdings from 478,212 down to 458,912 shares in the sequence shown. As the trades were executed under a Rule 10b5-1 plan and the filer offers to provide trade-level details on request, the disclosure meets regulatory transparency standards. The filing contains no other operational or financial data that would change company valuation metrics directly.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

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

X

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

MOSLEY WILLIAM D

(Last) (First) (Middle)

SEAGATE TECHNOLOGY HOLDINGS PLC

47488 KATO ROAD

(Street)

FREMONT CA 94538

(City) (State) (Zip)

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

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

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	CEO

3. Date of Earliest Transaction (Month/Day/Year)
09/02/2025

4. If Amendment, Date of 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

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)
			Code	V	Amount	(A) or (D)	Price
Ordinary Shares	09/02/2025		S		700(1)	D	$164.8021(2)	478,212	D
Ordinary Shares	09/02/2025		S		342	D	$165.6669(3)	477,870	D
Ordinary Shares	09/02/2025		S		400	D	$166.6025(4)	477,470	D
Ordinary Shares	09/02/2025		S		5,843	D	$168.2874(5)	471,627	D
Ordinary Shares	09/02/2025		S		5,715	D	$169.0589(6)	465,912	D
Ordinary Shares	09/02/2025		S		7,000	D	$170.1923(7)	458,912	D

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 Securities Underlying Derivative Security (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: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. All transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on February 20, 2025.

2. These Ordinary Shares were sold in multiple trades at prices ranging from $164.36 to $164.95. The price reported above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request to the SEC staff, the Issuer, or a security holder of the Issuer, full information regarding the number of shares and prices at which the transaction was effected.

3. These Ordinary Shares were sold in multiple trades at prices ranging from $165.43 to $166.09. The price reported above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request to the SEC staff, the Issuer, or a security holder of the Issuer, full information regarding the number of shares and prices at which the transaction was effected.

4. These Ordinary Shares were sold in multiple trades at prices ranging from $166.43 to $166.86. The price reported above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request to the SEC staff, the Issuer, or a security holder of the Issuer, full information regarding the number of shares and prices at which the transaction was effected.

5. These Ordinary Shares were sold in multiple trades at prices ranging from $167.63 to $168.62. The price reported above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request to the SEC staff, the Issuer, or a security holder of the Issuer, full information regarding the number of shares and prices at which the transaction was effected.

6. These Ordinary Shares were sold in multiple trades at prices ranging from $168.63 to $169.60. The price reported above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request to the SEC staff, the Issuer, or a security holder of the Issuer, full information regarding the number of shares and prices at which the transaction was effected.

7. These Ordinary Shares were sold in multiple trades at prices ranging from $169.64 to $170.61. The price reported above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request to the SEC staff, the Issuer, or a security holder of the Issuer, full information regarding the number of shares and prices at which the transaction was effected.

Remarks:

	/s/ Louis J. Thorson, Attorney-in-Fact for William D. Mosley	09/04/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* 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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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 Number.

FAQ

What insider activity did William D. Mosley report for STX on the Form 4?

Multiple open-market sales on 09/02/2025 executed under a Rule 10b5-1 plan, totaling 20,000 shares across six reported blocks with specified weighted-average prices.

Were the sales by Mosley pre-planned or spontaneous?

Pre-planned. The filing states the transactions were effected pursuant to a Rule 10b5-1 trading plan adopted February 20, 2025.

How many shares did Mosley own after these transactions?

The filing lists sequential post-transaction beneficial ownership figures after each block, ending at 458,912 shares following the last reported sale.

What price ranges were the shares sold at?

Explanatory notes report price ranges by block: approximately $164.36–$164.95, $165.43–$166.09, $166.43–$166.86, $167.63–$168.62, $168.63–$169.60, and $169.64–$170.61 with weighted averages shown for each block.

Who signed the Form 4 filing?

The Form 4 was signed by Louis J. Thorson, Attorney-in-Fact for William D. Mosley on 09/04/2025.