Sale of Common Stock by Officer

Michelle R. Mortensen, VP, Corp Sec & Chief of Staff at CALIFORNIA WATER SERVICE GROUP (CWT), reported the sale of 924 shares of common stock on December 23, 2025. The shares were sold at a price of $43.34 per share. This transaction resulted in a post-transaction ownership of 11,511.80 shares. The sale was executed in a single transaction, and full details regarding the number of shares and transaction price are available upon request to the SEC staff, the issuer, or a security holder.