Energy Recovery, Inc. (ERII) Insider Ownership

Historic Insider Ownership Trends

As of March 23, 2026, Energy Recovery's top three insider holders are Ole Peter Lorentzen (TenPercentOwner, 5.16Mn shares), Arve Hanstveit (Director, 550.22K shares), Robert Yu Lang Mao (Director, 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
Ole Peter Lorentzen 0 5,155,239 17 Sep, 2021
Arve Hanstveit 550,220 0 11 Mar, 2026
Robert Yu Lang Mao 248,935 0 24 May, 2024
David W Moon President And Ceo 233,069 0 19 Feb, 2026
Farshad Ghasripoor Chief Technology Officer 52,860 70,230 05 Feb, 2025
Rodney Clemente Svp, Water 116,008 0 06 Mar, 2026
William Yeung Chief Legal Officer 104,167 0 19 Feb, 2026
Michael S. Mancini Chief Financial Officer 75,051 0 19 Feb, 2026
Alexander J Buehler 66,328 0 06 Jun, 2025
Pamela L. Tondreau 55,890 0 06 Jun, 2025
Natarajan Ramanan Chief Technology Officer 52,565 0 06 Mar, 2026
Matthew Hostetler Chief Human Resources Officer 46,556 0 19 Feb, 2026
Joshua Ballard Chief Financial Officer 40,376 0 30 May, 2024
David W Moon President And Ceo 0 36,950 15 May, 2025
Joan Kai Chow 34,022 0 06 Jun, 2025
Robert Yu Lang Mao President And Ceo 0 32,166 04 Oct, 2021
Colin R Sabol 26,397 0 06 Jun, 2025
Olav Fjell 22,812 0 10 Jun, 2021
Sherif Foda 9,619 0 16 Sep, 2022
William Yeung Chief Legal Officer 0 5,568 17 Jun, 2022
Lisa A Pollina 4,007 0 13 Jun, 2023
Colin R Sabol 0 3,000 13 Nov, 2023
Joan Kai Chow 0 1,500 13 Nov, 2023

* 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
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
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 William Yeung Common Stock A 25,959 $0.00 104,167 D A
17 Feb, 2026 Rodney Clemente Common Stock A 45,626 $0.00 136,576 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 David W Moon Common Stock A 81,812 $0.00 233,069 D A
05 Feb, 2026 William Yeung Common Stock D 890 $14.59 78,854 D S
05 Feb, 2026 Rodney Clemente Common Stock D 724 $14.59 90,950 D S
06 Feb, 2026 William Yeung Common Stock D 646 $15.14 78,208 D S
30 Jan, 2026 Michael S. Mancini Common Stock D 4,798 $14.30 29,425 D F
30 Jan, 2026 Matthew Hostetler Common Stock D 3,359 $14.30 20,597 D F
30 Jan, 2026 David W Moon Common Stock D 17,160 $14.30 151,257 D F
28 Jan, 2026 William Yeung Common Stock D 7,271 $14.55 90,098 D S
30 Jan, 2026 Rodney Clemente Common Stock D 694 $14.65 100,071 D F