Energy Recovery, Inc. (ERII) Insider Ownership

Historic Insider Ownership Trends

As of May 30, 2026, the three largest insider holders of ERII are Ole Peter Lorentzen (TenPercentOwner, 5.16Mn shares), Arve Hanstveit (Director, 382.51K shares), Robert Yu Lang Mao (President And Ceo, 248.94K shares).

Top Direct Holders

Insider ownership data is derived from the last 60 months of Form 4 SEC filings.
Holder Position Shares (Direct) Shares (Indirect) Report Date
Robert Yu Lang Mao President And Ceo 248,935 0 24 May, 2024
David W Moon President And Ceo 233,069 0 19 Feb, 2026
Joan Kai Chow - 34,022 0 06 Jun, 2025
Alexander J Buehler - 66,328 0 06 Jun, 2025
Ole Peter Lorentzen - 0 5,155,239 17 Sep, 2021
Arve Hanstveit - 382,509 0 08 Apr, 2026
Sherif Foda - 9,619 0 16 Sep, 2022
Lisa A Pollina - 4,007 0 13 Jun, 2023
Rodney Clemente Svp, Water 116,008 0 06 Mar, 2026
William Yeung Chief Legal Officer 104,167 0 19 Feb, 2026
Pamela L. Tondreau - 55,890 0 06 Jun, 2025
Farshad Ghasripoor Chief Technology Officer 52,860 70,230 05 Feb, 2025
Joshua Ballard Chief Financial Officer 40,376 0 30 May, 2024
Michael S. Mancini Chief Financial Officer 75,051 0 19 Feb, 2026
Matthew Hostetler Chief Human Resources Officer 46,556 0 19 Feb, 2026
Natarajan Ramanan Chief Technology Officer 52,565 0 06 Mar, 2026

* Please note that the shares above only reflect shares from the fund portfolio and the institutional portfolio. Shares from the personal portfolio are excluded from this Institutional Ownership Page. See these insiders' latest transactions here on Insider Page.

Recent Insider Transactions

Detailed insider trading activity based on Form 4 SEC filings.
Download Data
Transaction Date Insider Name Security Class Transaction Type Shares Traded Price Shares Remaining Ownership Code
06 Apr, 2026 Arve Hanstveit Common Stock D 2,419 $10.29 382,509 D S
02 Apr, 2026 Arve Hanstveit Common Stock D 165,292 $10.14 384,928 D S
10 Mar, 2026 Arve Hanstveit Common Stock D 25,000 $10.96 550,220 D S
05 Mar, 2026 Arve Hanstveit Common Stock D 38,418 $10.71 586,802 D S
06 Mar, 2026 Arve Hanstveit Common Stock D 11,582 $10.62 575,220 D S
04 Mar, 2026 Rodney Clemente Common Stock D 20,568 $10.61 116,008 D S
05 Mar, 2026 Natarajan Ramanan Common Stock D 272 $10.57 52,565 D S
05 Mar, 2026 Natarajan Ramanan Common Stock D 272 $10.57 52,565 D S
05 Mar, 2026 Natarajan Ramanan Common Stock D 272 $10.57 52,565 D S
03 Mar, 2026 Natarajan Ramanan Common Stock D 2,724 $10.22 52,837 D F
03 Mar, 2026 Natarajan Ramanan Common Stock D 2,724 $10.22 52,837 D F
03 Mar, 2026 Natarajan Ramanan Common Stock D 2,724 $10.22 52,837 D F
17 Feb, 2026 Michael S. Mancini Common Stock A 45,626 $0.00 75,051 D A
17 Feb, 2026 Matthew Hostetler Common Stock A 25,959 $0.00 46,556 D A
17 Feb, 2026 Natarajan Ramanan Common Stock A 29,106 $0.00 55,561 D A
17 Feb, 2026 Michael S. Mancini Common Stock A 45,626 $0.00 75,051 D A
17 Feb, 2026 Natarajan Ramanan Common Stock A 29,106 $0.00 55,561 D A
17 Feb, 2026 Rodney Clemente Common Stock A 45,626 $0.00 136,576 D A
17 Feb, 2026 William Yeung Common Stock A 25,959 $0.00 104,167 D A
17 Feb, 2026 William Yeung Common Stock A 25,959 $0.00 104,167 D A