Audax Private Equity (“Audax”), a capital partner for middle and lower middle market companies, announced today it has completed the sale of Rensa Filtration (“Rensa” or the “Company”), a vertically integrated manufacturer, distributor, and service provider of consumable, high-purity air-filtration solutions for mission critical, high-growth applications. AEA Investors’ (“AEA”) Middle Market Private Equity team (“AEA MMPE”) and British Columbia Investment Management Corporation (“BCI”) acquired Rensa through a transaction that closed on October 8, 2026. Audax will maintain a minority stake in Rensa going forward, alongside Company management. Terms of the deal are not disclosed.

Founded by CEO Brandon Ost, Rensa is one of the largest U.S.-based privately held filtration companies. The Company specializes in manufacturing highly engineered, tight-tolerance air filters used in critical-environment applications, from data centers and power generation to food processing, healthcare and life sciences, semiconductor manufacturing, and other cleanroom environments.

“Audax Private Equity understood our mission from the start and invested behind our vision for growth, helping to build out our team and expand our solution set while reinforcing our value proposition as a true thought partner to our clients,” noted Rensa Chief Executive Officer and Founder Brandon Ost. “We’re excited to build on this momentum alongside AEA and BCI and looking forward to pursuing the compelling opportunity set in front of us.”

Since Audax Private Equity’s strategic investment in Rensa in August 2022, the Company opened two de novo manufacturing facilities in Nevada and Illinois, built out its service locations to create a national footprint, and completed ten acquisitions that added new technology, helped Rensa enter new end markets and geographies, and provided critical exposure across the value chain.

“Rensa, we believe, provides a case study in how we seek to build strategic assets,” noted Joe Rogers, Partner at Audax Private Equity. “Brandon and the management team recognized that by positioning the Company as a thought partner to clients across the full product lifecycle – from manufacturing and distribution to on-site installation and testing — Rensa could distinguish itself through an expansive and proprietary product set tailored to mission-critical applications. We invested behind this strategy, brought operational resources to bear, and positioned the Company to move with speed and conviction to drive organic and inorganic growth.”

“We’re proud of what we accomplished together with the entire Rensa team,” added Audax Private Equity Managing Director Matthew Gosselin. “This is another example of how we seek to enable, create and protect value through the disciplined execution of the Audax Value Agenda. We look forward to continuing to support the business in partnership with AEA and BCI as it enters its next phase of growth.”

The sale of Rensa represents the eighth realization either announced or completed by Audax Private Equity’s Flagship strategy in 2026, and the tenth exit, including sales under contract, across the PE platform over the past 12 months. Collectively, the sale activity over the trailing 12-month period represents approximately $15 billion in total transaction value.

Lincoln International and Baird acted as financial advisors to Audax, and Ropes & Gray served as legal counsel.

ABOUT AUDAX PRIVATE EQUITY:

Headquartered in Boston, with offices in San Francisco, New York, London and Hong Kong, Audax Private Equity is a leading private equity platform focused on investing across the North American middle market. Our objective is to accelerate value creation through our Buy & Build strategy and the Audax Value Agenda™, a holistic framework that seeks to enable, create, and protect value across every stage of the investment lifecycle. As of July 2026, Audax Private Equity had approximately $20.1 billion of assets under management and, since inception in 1999, has invested in more than 180 platforms and more than 1,500 add-on acquisitions. For more information, visit www.audaxprivateequity.com or follow us on LinkedIn.

ABOUT RENSA FILTRATION:

Rensa is a leading designer, manufacturer and distributor of highly engineered, consumable air filtration solutions focused on helping protect people and systems in critical environments and applications. Rensa offers a wide range of standard and customized air filtration products that provide best-in-class filtration performance and energy savings in education, healthcare and high-tech manufacturing facilities. Rensa also offers specialized air filtration solutions for data centers and activated carbon filters for the removal of odors and molecular contamination in museums, airports and healthcare facilities. For more information, visit rensafiltration.com or follow us on LinkedIn.

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