Seagate Technology CEO William Mosley Sells $10.29M in Shares Under 10b5-1 Plan

Executive Summary

On October 2, 2026, Seagate Technology Holdings plc (NASDAQ: STX) filed a Form 4 disclosing open-market sales of Ordinary Shares by Chief Executive Officer and Director William D. Mosley. Across 16 tranches on October 1, 2026, Mosley disposed of an aggregate of 11,002 shares for total proceeds of approximately $10,293,464, at weighted average prices ranging from $929.01 to $945.97 per share (overall weighted average of $935.60).

Transaction Breakdown & 10b5-1 Plan

• Security: Ordinary Shares
• Total Shares Sold: 11,002
• Effective Price Range: $928.44 – $946.34
• Total Consideration: $10,293,464.47
• Rule 10b5-1 Adoption: All sales were executed pursuant to a written Rule 10b5-1 trading plan adopted on February 18, 2026.

Ownership Context & Trading Significance

• Prior Direct Holdings: 373,110.25 shares
• Shares Sold: 11,002 shares (~2.95% reduction in direct holdings)
• Post-Transaction Holdings: 362,108.25 shares

Significance Assessment: Medium
While the gross dollar volume exceeds $10 million and involves the chief executive officer, the market impact is tempered significantly by the structured nature of the divestment. The sales represented less than 3% of Mosley's direct equity position and were executed strictly under an affirmative Rule 10b5-1 defense established nearly eight months prior.