Guidewire Software CEO Mike Rosenbaum Files Form 144 for $202.8K Common Stock Sale

Executive Summary

On October 13, 2026, Guidewire Software, Inc. (NYSE: GWRE) filed a Form 144 on behalf of CEO and Director Mike Rosenbaum. The filing discloses a proposed sale of 1,200 shares of common stock with an aggregate market value of approximately $202,764, representing an average price of $168.97 per share. The approximate date of sale was October 12, 2026, through broker-dealer Morgan Stanley Smith Barney LLC.

Transaction & Trading Plan Details

• Securities to be Sold: 1,200 shares of common stock acquired on September 15, 2023, via performance share vestings directly from the issuer.
• Aggregate Market Value: $202,764.00.
• Rule 10b5-1 Plan: The sale was executed pursuant to a pre-arranged Rule 10b5-1 trading plan adopted on October 14, 2025.
• Filing Timing: Remarks clarify that sales executed on October 12, 2026, were reported on October 13, 2026, due to the federal holiday closure of the EDGAR system on October 12.

Historical Selling Activity

A review of securities sold in the past three months shows a consistent, recurring weekly schedule of 1,200-share sales by Mr. Rosenbaum under the 10b5-1 plan, alongside a larger transaction of 72,290 shares on September 17, 2026 ($10.44M in gross proceeds).

Market Impact & Significance

• Trading Significance: Low.
• Market Impact: With Guidewire Software having 81,992,669 shares outstanding, this 1,200-share transaction represents less than 0.0015% of outstanding shares. Given the programmatic nature under a long-standing 10b5-1 plan, the sale carries minimal informational signal and negligible market impact.