UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ Quarterly Report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: September 30, 2023 ☐ Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Commission File Number: 1-33026 Commvault Systems, Inc. (Exact name of registrant as specified in its charter) Delaware 22-3447504 (State or other jurisdiction of (I.R.S. Employer incorporation or o ...