Form 4 Filing for William Geoffrey Haydon

This filing details a Form 4 submission by William Geoffrey Haydon, President of Cust & Field Ops at COMMVAULT SYSTEMS INC. On April 13, 2026, Haydon was granted 64,543 shares of Common Stock with a transaction price of $0.0. These shares are subject to a 3-year vesting schedule, with 33% vesting on the first anniversary and the remaining vesting in three-month increments thereafter. Following this transaction, Haydon owns 65,570 shares of Common Stock. The filing was signed by Danielle Abrahamsen, Attorney-in-Fact, on April 15, 2026.