Key Takeaways
- • AEA Investors' Middle Market Private Equity team and British Columbia Investment Management Corporation (BCI) acquired Rensa Filtration in a transaction that closed on October 8, 2026, per Audax Private Equity's announcement.
- • Audax Private Equity, which invested in Rensa in 2022, will retain a minority stake alongside company management after the sale.
- • The deal followed ten add-on acquisitions completed under Audax's Buy & Build strategy, and Rensa is described as one of the largest privately held U.S. filtration companies.
- • Financial terms were not disclosed.
- • Rensa manufactures tight-tolerance, high-purity air filters for data centers, power generation, healthcare, life sciences, semiconductor manufacturing, and other cleanroom environments.
Summary
Audax Private Equity, a capital partner for middle and lower middle market companies, has completed the sale of Rensa Filtration, a vertically integrated manufacturer, distributor, and service provider of consumable, high-purity air-filtration solutions for mission-critical, high-growth applications. According to Audax's announcement, AEA Investors' 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 alongside company management. Terms of the transaction were not disclosed.
The sale comes four years after Audax first invested in the company, which was acquired in August 2022, and follows ten add-on acquisitions completed as part of a comprehensive Buy & Build strategy. Rensa's acquisitions have included Air Filters Northwest and IREMA-Filter GmbH in Germany, according to Audax-related announcements in the publisher's database.
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 for critical-environment applications, including data centers, power generation, food processing, healthcare and life sciences, semiconductor manufacturing, and other cleanroom environments.
In the announcement, Rensa Chief Executive Officer and Founder Brandon Ost credited Audax with understanding the company's mission from the outset and with supporting the build-out of its team and product offering. He said the company's value proposition as a "true thought partner" to clients had been reinforced during Audax's ownership. Ost said Rensa looks forward to building on that momentum with AEA and BCI and pursuing the opportunities ahead.
The sale comes four years after Audax first invested in the company, which was acquired in August 2022, and follows ten add-on acquisitions completed as part of a comprehensive Buy & Build strategy. Rensa's acquisitions have included Air Filters Northwest and IREMA-Filter GmbH in Germany, according to Audax-related announcements in the publisher's database.
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 for critical-environment applications, including data centers, power generation, food processing, healthcare and life sciences, semiconductor manufacturing, and other cleanroom environments.
In the announcement, Rensa Chief Executive Officer and Founder Brandon Ost credited Audax with understanding the company's mission from the outset and with supporting the build-out of its team and product offering. He said the company's value proposition as a "true thought partner" to clients had been reinforced during Audax's ownership. Ost said Rensa looks forward to building on that momentum with AEA and BCI and pursuing the opportunities ahead.
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