Seagate CEO William D. Mosley Exercises Options and Sells $17.4M in Shares Under 10b5-1 Plan

Executive Summary

On October 1, 2026, William D. Mosley, Chief Executive Officer and Director of Seagate Technology Holdings plc (STX), conducted a series of transactions involving the exercise of stock options and subsequent open-market share sales. Mosley exercised options to acquire 14,000 ordinary shares at a strike price of $46.23 per share and disposed of a total of 18,998 ordinary shares across 28 separate market tranches at prices ranging between $897.79 and $928.36, generating gross sale proceeds of approximately $17.42 million.

Transaction Details

• Option Exercise: 14,000 non-qualified stock options exercised at $46.23 per share, leaving 83,100 derivative securities remaining under that award.
• Open-Market Dispositions: A total of 18,998 ordinary shares sold at a volume-weighted average price of approximately $916.77 per share.
• Total Sale Proceeds: Approximately $17,416,887.
• Pre-Planned Execution: All transactions were conducted pursuant to a pre-established Rule 10b5-1 trading plan adopted on February 18, 2026.

Ownership Impact & Significance

• Significance Level: Medium
• While the headline sale value is significant at over $17.4 million, market impact is tempered because the sales were executed under an affirmative Rule 10b5-1 trading plan established more than seven months prior.
• Following these transactions, Mosley continues to hold a substantial stake of 373,110.25 ordinary shares directly, retaining meaningful equity alignment with shareholders.