Form 4 Filing for Energy Recovery, Inc.

This filing details a transaction by Arve Hanstveit, a director at Energy Recovery, Inc. On April 6, 2026, Mr. Hanstveit disposed of 2,419 shares of Common Stock at a price of $10.29 per share. This sale was executed by a broker to satisfy a margin call, with the shares having been previously pledged as collateral. Following this transaction, Mr. Hanstveit has 382,509 shares remaining. The filing also notes that Mr. Hanstveit is the sole trustee for two irrevocable trusts, the Sophie Hanstveit Irrevocable Trust and the Natasha Hanstveit Irrevocable Trust, each holding 60,000 shares of Common Stock, where he exercises sole voting and investment power. A separate exhibit contains a Power of Attorney appointing David Moon, Michael Mancini, and William Yeung as attorneys-in-fact to handle Section 16 filings.