[Form 4] Energy Recovery, Inc. Insider Trading Activity

Rhea-AI Filing Summary

William Yeung, Chief Legal Officer of Energy Recovery, Inc. (ERII), reported transactions dated 09/11/2025. He exercised employee stock options with an $8.95 exercise price to acquire 30,877 shares and, on the same date, sold 33,554 shares at an average weighted price of $14.51 per share (trade prices ranged $14.40–$14.65). After these transactions, he beneficially owned 97,369 shares. The sale was executed under a Rule 10b5-1 trading plan and the Form 4 was signed on 09/15/2025.

Positive

• Exercise of options to acquire 30,877 shares at a fixed $8.95 exercise price, demonstrating continued insider ownership
• Sale executed under a Rule 10b5-1 plan, which indicates the disposition followed a pre-established trading program

Negative

• Insider sold 33,554 shares, reducing immediate shareholdings via open-market transactions
• Weighted average sale price of $14.51 may indicate partial monetization of position despite continued ownership

Insights

Securities Analyst

TL;DR: Insider exercised options and sold shares under a prearranged 10b5-1 plan; net holdings remain material.

The filing shows an exercise of employee stock options (30,877 shares at $8.95) and a contemporaneous sale of 33,554 shares at a weighted average price of $14.51. The seller discloses the sale occurred under a Rule 10b5-1 plan, which typically indicates preplanned disposition rather than opportunistic trading. Post-transaction beneficial ownership is reported at 97,369 shares. For investors, this represents routine insider liquidity and continued meaningful ownership by an officer.

Corporate Governance Expert

TL;DR: Transactions are documented and compliant with Rule 10b5-1; disclosure is complete for reported items.

The Form 4 includes required details: transaction codes, prices, option vesting information, and an explicit statement that the sale was effected pursuant to a Rule 10b5-1 trading plan. The report also explains the weighted average sale price and offers to provide price-by-price detail upon request. The signature and dates are present, indicating proper filing formalities were observed.

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

1. Name and Address of Reporting Person^*

Yeung William

(Last) (First) (Middle)

C/O ENERGY RECOVERY, INC.

1717 DOOLITTLE DRIVE

(Street)

SAN LEANDRO CA 94577

(City) (State) (Zip)

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

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

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

3. Date of Earliest Transaction (Month/Day/Year)
09/11/2025

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

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

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

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	09/11/2025		M		30,877	A	$8.95	130,923	D
Common Stock	09/11/2025		S		33,554	D	$14.51(1)	97,369(2)	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
Employee Stock Option (Right to Buy)	$8.95	09/11/2025		M			30,877	(3)	06/19/2026	Common Stock	30,877	$8.95	15,454	D

Explanation of Responses:

1. This amount represents the weighted average sales price of multiple trades ranging from $14.40 to $14.65 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 sold at each separate price upon request.

2. These transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person.

3. 25% of the shares became vested and exercisable on the 1st anniversary of the vesting start date of 06/20/2016; Thereafter, the remaining 75%, will vest and become exercisable 1/36th per month. The options become fully vested and exercisable on 06/20/2020.

Remarks:

	/s/ William Yeung	09/15/2025
	** 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.

FAQ

What transactions did William Yeung report on Form 4 for ERII?

He exercised 30,877 options at an $8.95 exercise price and sold 33,554 shares on 09/11/2025.

How many ERII shares does William Yeung beneficially own after these transactions?

The Form 4 reports he beneficially owned 97,369 shares following the reported transactions.

At what price were the shares sold and how was the sale executed?

The shares were sold at a weighted average price of $14.51 (individual trades ranged $14.40–$14.65) and were effected pursuant to a Rule 10b5-1 trading plan.

When were the transactions and when was the Form 4 signed?

The transactions occurred on 09/11/2025 and the Form 4 was signed on 09/15/2025.

What option vesting information is disclosed in the filing?

The filing states the options had vesting that began 06/20/2016 (25% on the first anniversary) and fully vested on 06/20/2020; it also notes monthly vesting thereafter for remaining shares in the earlier schedule.