The co-founders of Getaroom have sold a majority stake in the business-to-business hotel and vacation rental provider to private equity firm Court Square Capital Partners, whose other holdings include car rental company Auto Europe.

Getaroom President Bob Diener told Skift Tuesday that he and his business partner for the past 35 years, Getaroom CEO Dave Litman, still maintain a substantial minority stake in Getaroom, and sold the larger stake to help the company reach the next level, including accelerating international expansion.

Getaroom and New York-based Court Square did not disclose additional terms of the deal. With 300-500 employees, one company-owned call center, and four additional calls centers, Getaroom will do more than billion in gross sales in 2018, Diener said.

He added that Getaroom has been self-funded until now, and has been profitable for the past five or six years.

Dallas-based Getaroom launched in 2009 as a hotel-booking site for consumers, but soon thereafter pivoted into a business-to-business provider of hotels — and lately vacation rentals, too — to affiliates, including online travel agencies, metasearch sites, airlines, destination sites, and membership clubs, for example.

 Under the Getaroom business model, it contracts with hotels for published rates, unpublished rates sold through its call centers, and member-only rates for people who belong to membership clubs.