Director Pamela Tondreau adds 20,000 Energy Recovery (ERII) shares via trust

Rhea-AI Filing Summary

Energy Recovery, Inc. director Pamela L. Tondreau reported an open-market purchase of 20,000 shares of common stock on May 13, 2026 through the Bruce-Tondreau Living Trust. The weighted average purchase price was $8.342 per share, with individual trades between $8.335 and $8.35. Following the purchase, the filing shows 37,362 shares held indirectly by the trust and a separate direct holding entry of 38,528 shares in her name. A footnote explains the trust total includes the 20,000 shares bought on May 13, 2026 plus 17,362 shares transferred to the trust in January 2026, for which she may be deemed to have beneficial ownership.

Insights

Insider trading analyst

Director adds 20,000 ERII shares via trust in a routine-sized open-market buy.

Director Pamela L. Tondreau reported an open-market purchase of 20,000 Energy Recovery common shares at a weighted average price of $8.342 on May 13, 2026, executed through the Bruce-Tondreau Living Trust. This is classified as a straightforward open-market buy (code P).

The filing also shows 38,528 shares held directly and 37,362 shares held indirectly by the trust after the reported transactions, indicating that the 20,000-share purchase is modest relative to her disclosed positions. A footnote notes a prior transfer of 17,362 shares to the trust in January 2026, which helps explain the indirect total.

There is no indication in the excerpt of a Rule 10b5-1 plan or derivative activity, and 0% of the reported transactions involve sales. From this single filing, the visible pattern is a net-buy of 20,000 shares, which appears routine in scale given the reported direct and indirect holdings.

Insider Trade Summary

Net Buyer: 20,000 shares ($166,840)

Net Buy 2 txns

Insider TONDREAU PAMELA L.

Role null

Bought 20,000 shs ($167K)

Type	Security	Shares	Price	Value
Purchase	Common Stock	20,000	$8.342	$167K
holding	Common Stock	--	--	--

Holdings After Transaction: Common Stock — 37,362 shares (Indirect, The Bruce-Tondreau Living Trust Dtd October 11, 2018); Common Stock — 38,528 shares (Direct, null)

Footnotes (1)

1. This amount represents the weighted average purchase price of multiple trades ranging from $8.335 to $8.35 per share. The reporting person undertakes to provide the SEC Staff, Energy Recovery, Inc. or a shareholder of Energy Recovery, Inc. full information about the number of shares purchased at each separate price upon request. This total reflects the 20,000 shares purchased on May 13, 2026, as well as 17,362 shares the Reporting Person transferred in January 2026 to the Bruce-Tondreau Living Trust Dtd October 11, 2018, of which the Reporting Person and their spouse are beneficiaries. The Reporting Person may be deemed to have beneficial ownership of the shares held by the Trust.

Key Figures

Shares purchased: 20,000 shares Weighted average purchase price: $8.342 per share Trade price range: $8.335–$8.35 per share +4 more

7 metrics

Shares purchased 20,000 shares Open-market purchase on May 13, 2026 via trust

Weighted average purchase price $8.342 per share Energy Recovery common stock, May 13, 2026

Trade price range $8.335–$8.35 per share Underlying trades for the 20,000-share purchase

Direct holdings after transaction 38,528 shares Common stock held directly by Pamela L. Tondreau

Indirect trust holdings after transaction 37,362 shares Common stock held by Bruce-Tondreau Living Trust

Net buy shares 20,000 shares Net buy direction in transaction summary

Prior transfer to trust 17,362 shares Transferred to trust in January 2026

Key Terms

open-market purchase, weighted average purchase price, beneficial ownership, Living Trust, +1 more

5 terms

open-market purchase financial

"transaction_action": "open-market purchase""

An open-market purchase is when an investor or a company buys shares on a public stock exchange at the going market price, rather than through a private deal. It matters to investors because these purchases change how many shares are available, can push the stock price up or signal confidence from large buyers, and often affect per-share metrics like earnings—think of it like someone buying lots of apples off a grocery shelf, reducing supply and potentially raising the price.

weighted average purchase price financial

"represents the weighted average purchase price of multiple trades"

The weighted average purchase price is the average cost per share you paid across multiple buys, calculated so larger purchases count more than smaller ones. Imagine buying apples at different prices: the overall price you effectively paid depends on how many apples you bought at each price. Investors use it to measure true cost basis, calculate gains or losses, decide when to sell, and manage taxes and portfolio performance.

beneficial ownership financial

"The Reporting Person may be deemed to have beneficial ownership"

Beneficial ownership means the person or entity that actually enjoys the benefits of owning shares or other assets — such as receiving dividends, voting rights, or price gains — even if the legal title is held in another name. For investors it matters because knowing who truly controls and profits from a company reveals who can influence decisions, exposes potential conflicts of interest or hidden concentration of power, and affects transparency and risk in the stock.

Living Trust financial

"The Bruce-Tondreau Living Trust Dtd October 11, 2018"

indirect ownership financial

""ownership_type": "indirect""

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

TONDREAU PAMELA L.

(Last) (First) (Middle)

C/O ENERGY RECOVERY, INC.

1717 DOOLITTLE DRIVE

(Street)

SAN LEANDRO CALIFORNIA 94577

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Energy Recovery, Inc. [ ERII ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/13/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	05/13/2026		P		20,000	A	$8.342(1)	37,362(2)	I	The Bruce-Tondreau Living Trust Dtd October 11, 2018
Common Stock								38,528	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. This amount represents the weighted average purchase price of multiple trades ranging from $8.335 to $8.35 per share. The reporting person undertakes to provide the SEC Staff, Energy Recovery, Inc. or a shareholder of Energy Recovery, Inc. full information about the number of shares purchased at each separate price upon request.

2. This total reflects the 20,000 shares purchased on May 13, 2026, as well as 17,362 shares the Reporting Person transferred in January 2026 to the Bruce-Tondreau Living Trust Dtd October 11, 2018, of which the Reporting Person and their spouse are beneficiaries. The Reporting Person may be deemed to have beneficial ownership of the shares held by the Trust.

Remarks:

Exhibit 24

	/s/ William Yeung, Attorney-in-fact for Pamela Tondreau	05/14/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transaction did Energy Recovery (ERII) report for Pamela L. Tondreau?

Energy Recovery (ERII) reported that director Pamela L. Tondreau bought 20,000 common shares. The shares were acquired in an open-market transaction on May 13, 2026, through the Bruce-Tondreau Living Trust at a weighted average price of $8.342 per share.

At what price did the ERII director’s trust buy shares on May 13, 2026?

The Bruce-Tondreau Living Trust bought ERII shares at a weighted average of $8.342. A footnote states this reflects multiple trades in Energy Recovery common stock, with prices ranging from $8.335 to $8.35 per share on May 13, 2026.

How many Energy Recovery (ERII) shares does Pamela L. Tondreau hold directly after this Form 4?

The filing reports Pamela L. Tondreau directly holds 38,528 ERII common shares. This direct holding is recorded in a separate line item from the trust, which is classified as indirect ownership, and reflects her position after the reported transactions.

What is the Bruce-Tondreau Living Trust’s Energy Recovery (ERII) holding after the purchase?

The Bruce-Tondreau Living Trust is shown holding 37,362 ERII shares after the transaction. A footnote explains this total includes the 20,000 shares purchased on May 13, 2026 and 17,362 shares transferred to the trust in January 2026.

Did the Energy Recovery (ERII) Form 4 show any insider share sales?

No insider sales are reported in this ERII Form 4 excerpt. The transaction summary shows one open-market purchase of 20,000 shares and no sales, gifts, tax withholdings, or derivative exercises for director Pamela L. Tondreau.