Energy Recovery (ERII) appoints board member Alex Buehler as interim CEO
Filing Impact
Filing Sentiment
Form Type
8-K
Rhea-AI Filing Summary
Energy Recovery, Inc. announced a leadership transition as President and Chief Executive Officer David Moon accelerated his previously announced retirement and resigned from all positions, effective May 26, 2026. The company states his decision was not related to any disagreement with management or the Board.
On the same date, Board member and former CFO Alex Buehler, age 51, was appointed Interim President and CEO and will serve until a permanent successor is selected. He will remain on the Board but step down from the Compensation and Audit Committees, with Director Arve Hanstveit becoming Audit Committee Chair. An executive search firm has been engaged to identify the next permanent CEO, and the company issued a press release on May 28, 2026 describing the transition.
Positive
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Insights
Energy Recovery moves to an interim CEO while formal search continues.
Energy Recovery has shifted from a planned retirement to an accelerated CEO departure, with David Moon resigning effective May 26, 2026. The company explicitly notes there is no disagreement with management or the Board, framing this as a personal-timing change rather than a strategic rupture.
The Board named long-time insider and former CFO Alex Buehler as Interim President and CEO, leveraging his prior executive experience and board tenure to provide continuity. Governance-wise, he is stepping off the Compensation and Audit Committees, and Arve Hanstveit becomes Audit Committee Chair, which helps maintain committee independence while Buehler holds dual roles.
An external executive search firm is already engaged to identify the next permanent CEO, indicating a structured process is in place. Investors will likely focus on future disclosures around the final CEO selection and any strategic updates that accompany that appointment.
8-K Event Classification
2 items: 5.02, 9.01
2 items
Item 5.02
Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers
Governance
Key personnel changes including departures, elections, or appointments of directors and executive officers.
Item 9.01
Financial Statements and Exhibits
Exhibits
Financial statements, pro forma financial information, and exhibit attachments filed with this report.
Key Figures
Effective CEO resignation date: May 26, 2026
Interim CEO appointment date: May 26, 2026
Interim CEO age: 51 years
+3 more
6 metrics
Effective CEO resignation date
May 26, 2026
David Moon’s resignation as President, CEO, and director
Interim CEO appointment date
May 26, 2026
Board appointed Alex Buehler as Interim President and CEO
Interim CEO age
51 years
Age of Alex Buehler at time of appointment
Press release date
May 28, 2026
Company press release announcing Buehler’s appointment
Exhibit 99.1
Press Release
Filed as an exhibit describing CEO transition
Exhibit 104
Cover Page XBRL
Inline XBRL cover page data tags
Key Terms
Interim President and Chief Executive Officer, Audit Committee Chair, Compensation Committee, executive search firm, +2 more
6 terms
Interim President and Chief Executive Officer financial
"appointed Mr. Alex Buehler, age 51, to serve as the Company’s Interim President and Chief Executive Officer"
Audit Committee Chair financial
"Mr. Arve Hanstveit has been appointed as the new Audit Committee Chair"
Compensation Committee financial
"will retain his board seat during the transition but will step down from the Compensation and Audit Committees"
A compensation committee is a group within a company's leadership responsible for setting and reviewing how much top executives and employees are paid, including salaries, bonuses, and benefits. It matters to investors because fair and effective pay decisions can influence a company's performance, leadership motivation, and overall governance, helping ensure that the company’s management is aligned with shareholders’ interests.
executive search firm financial
"the Board has engaged a leading executive search firm to conduct a search for the company's next CEO"
Regulation S-K regulatory
"related party transactions with Mr. Buehler that are reportable under Item 5.02 of and Item 404(a) of Regulation S-K"
A set of U.S. Securities and Exchange Commission rules that tell public companies which narrative and qualitative details must be disclosed in filings, such as risk factors, management discussion, executive pay, legal proceedings and business description. Think of it as a standardized checklist or blueprint that ensures investors get the same types of background information from every company so they can compare risks, management quality and strategy before making investment decisions.
Inline XBRL regulatory
"Cover Page Interactive Data File - the cover page XBRL tags are embedded within the Inline XBRL document"
Inline XBRL is a file format for financial filings that embeds machine-readable data tags directly inside the human-readable report, so the same document can be read by people and parsed by software. For investors it makes extracting, comparing and verifying financial numbers faster and more reliable—like a grocery list where each item also has a barcode—reducing manual errors and speeding up analysis.
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 8-K
Current Report
Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934
Date of Report (Date of earliest event reported): May 28, 2026
(Exact Name of Registrant as Specified in its Charter)
| (State or Other Jurisdiction of Incorporation) | (Commission File Number) | (I.R.S. Employer Identification No.) | ||||||||||||
(Address of Principal Executive Offices) (Zip Code)
(510 ) 483-7370
(Registrant’s telephone number, including area code)
Not applicable
(Former Name or Former Address, if Changed Since Last Report)
Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:
Securities registered pursuant to Section 12(b) of the Act:
| Title of each class | Trading Symbol(s) | Name of each exchange on which registered | ||||||||||||
Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 or Rule 12b-2 of the Securities Exchange Act of 1934.
Emerging growth company ☐
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐
Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.
Departure of President and Chief Executive Officer
On May 25, 2026, Mr. David Moon informed the Board of Directors (the “Board”) of Energy Recovery, Inc. (the “Company”) of his intention to accelerate his previously announced retirement and resign from all positions within the Company, including as President, Chief Executive Officer and as a member of the Board, effective on May 26, 2026. Mr. Moon’s decision to resign from the Company was not related to any disagreement with the Company's management or the Board on any matter related to the Company's operations, policies or practices.
Appointment of Interim President and Chief Executive Officer
On May 26, 2026, the Board appointed Mr. Alex Buehler, age 51, to serve as the Company’s Interim President and Chief Executive Officer to serve in these positions until a permanent successor is appointed by the Board. Mr. Buehler will retain his board seat during the transition but will step down from the Compensation and Audit Committees, including his role as Audit Committee Chair. Mr. Arve Hanstveit has been appointed as the new Audit Committee Chair.
Mr. Buehler brings deep familiarity with Energy Recovery and the water industry. Mr. Buehler served as Energy Recovery’s CFO from 2011 to 2014 and has been a member of the Board since 2015. Mr. Buehler most recently served as CEO of Integrated Water Services from October 2022 to October 2025, as Interim CEO of LiqTech International from March 2022 to September 2022, and earlier as President and CEO of Brock Group from February 2021 to December 2021. Prior to that, Mr. Buehler held many executive level roles at various industrial and infrastructure companies. He currently serves as a Chairman of the Board for LiqTech Systems and previously served as a Board member for Viscount Systems. Mr. Buehler received a Bachelor of Science in civil engineering from the United States Military Academy at West Point and an MBA from the Wharton School at the University of Pennsylvania.
Mr. Buehler’s compensation in connection with his role as Interim President and Chief Executive Officer of the Company has not yet been determined, and will be set by the Company’s Compensation Committee at a later date, at which time the Company will file an amendment to this Current Report on Form 8-K to disclose the material terms.
There are no family relationships between Mr. Buehler and any of the executive officers or directors of the Company, and there are no arrangements or understandings between Mr. Buehler and any other person pursuant to which he was appointed as an officer of the Company. There are no actual or proposed related party transactions with Mr. Buehler that are reportable under Item 5.02 of Form 8-K and Item 404(a) of Regulation S-K.
On May 28, 2026, the Company issued a press release announcing Mr. Buehler’s appointment. A copy of such press release is attached hereto as Exhibit 99.1 and incorporated by reference herein.
Item 9.01 Financial Statements and Exhibits.
(d) Exhibits
| Exhibit Number | Description | |||||||
99.1 | Press Release, issued by Energy Recovery on May 28, 2026 | |||||||
| 104 | Cover Page Interactive Data File - the cover page XBRL tags are embedded within the Inline XBRL document. | |||||||
Signatures
Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.
| Energy Recovery, Inc. | ||||||||||||||
| Date: | May 28, 2026 | By: | /s/ William Yeung | |||||||||||
| William Yeung | ||||||||||||||
| Chief Legal Officer | ||||||||||||||
Exhibit 99.1
Energy Recovery Announces Appointment of Alex Buehler as Interim President and Chief Executive Officer
SAN LEANDRO, Calif. — May. 28, 2026 — Energy Recovery (Nasdaq: ERII), a global leader in energy-efficient technology enabling affordable, reliable water and reduced emissions, today announced that current Board of Directors member Alex Buehler has been named Interim President and CEO, effective immediately, until the permanent position has been filled.
For personal reasons, President and CEO David Moon has decided to accelerate the timing of his previously announced retirement. The Board thanks Mr. Moon for his contribution to the company and wishes him well in retirement.
As previously announced, the Board has engaged a leading executive search firm to conduct a search for the company's next CEO and will evaluate all qualified candidates, internal and external.
Mr. Buehler brings deep familiarity with Energy Recovery and the water industry. He served as Energy Recovery’s CFO from 2011 to 2014 and is a current member of Energy Recovery’s Board. Mr. Buehler most recently served as CEO of Integrated Water Services and earlier as Interim CEO of LiqTech International, which specializes in advanced membranes and filters composed of silicon carbide ceramics. He currently serves as Chairman of the Board for LiqTech Systems and previously served as a Board member for Viscount Systems.
Mr. Buehler received a Bachelor of Science in civil engineering from the United States Military Academy at West Point and an MBA from the Wharton School at the University of Pennsylvania.
Mr. Buehler will retain his Board seat but step down from his positions on the Compensation and Audit Committees, including his role as Audit Chair. Director Arve Hanstveit has been appointed as Audit Chair.
About Energy Recovery
Energy Recovery (Nasdaq: ERII) designs and manufactures world-class energy-saving technology for critical infrastructure that communities rely on every day, driving a more resilient and sustainable future. Grounded in more than 30 years of leadership in the desalination industry, today we use our proprietary pressure exchanger technology to help customers in multiple industries improve their operations and lower their emissions. Headquartered in the San Francisco Bay Area, we operate manufacturing and R&D facilities throughout California, with sales and on-site technical support available globally.
Investor Relations
ir@energyrecovery.com
Press Inquiries
pr@energyrecovery.com
FAQ
Why did Energy Recovery (ERII) change its CEO in May 2026?
Energy Recovery’s President and CEO David Moon chose to accelerate his previously announced retirement, resigning effective May 26, 2026. The company stated his departure was for personal reasons and not due to any disagreement with management, operations, policies, or practices.
Who is the new Interim CEO of Energy Recovery (ERII)?
Board member and former CFO Alex Buehler has been appointed Interim President and CEO, effective May 26, 2026. He has long experience with Energy Recovery and prior leadership roles at Integrated Water Services, LiqTech International, and Brock Group.
Will Alex Buehler remain on the Energy Recovery (ERII) Board?
Yes. Alex Buehler will retain his Board seat while serving as Interim President and CEO. However, he is stepping down from the Compensation and Audit Committees, including his prior role as Audit Committee Chair, to maintain sound governance practices.
Who is now Audit Committee Chair at Energy Recovery (ERII)?
Director Arve Hanstveit has been appointed as the new Audit Committee Chair. This change follows Alex Buehler’s move to Interim President and CEO and his resignation from the Audit Committee and its chair role to avoid overlapping management and oversight responsibilities.
How is Energy Recovery (ERII) searching for a permanent CEO?
The Board has engaged a leading executive search firm to find the next permanent CEO. They plan to evaluate all qualified internal and external candidates, aiming for an orderly succession while Alex Buehler serves as Interim President and CEO during the transition.