Europe’s biggest pay TV platform Sky has made an investment in L.A.-based TV4 Entertainment, which owns a burgeoning portfolio of special-interest television channels. The channels,  which include DocComTV aimed at documentary fans; All Warrior Network; Motorland, a network for car enthusiasts as well as the Ultimate Champion Network, which has programming for combat sports fans, are distributed across multiple online platforms in the U.S., including Hulu, Amazon, Sony, Vimeo, YouTube and Roku.

TV4’s portfolio reaches millions of users every month. The company is looking to add more than 30 new channels to its current dozen-plus roster. The company’s strategy is to acquire and aggregate high-quality video content into recognisable channel brands. With more than 200 content partners, TV4 has licensed more than 5,000 feature length and short form titles as well as many TV and web series.

Sky has maintained a policy of investing in innovative start-ups, including online sports network Whistle Sports, online video aggregator Pluto TV and the U.S. ad tech firm Sharethrough. Sky has also previously invested streaming service provider Roku, the immersive 360 video specialists Jaunt and the OTT video delivery firm 1 Mainstream.

Sky became Europe’s biggest single pay TV operator in November last year following its acquisition of Sky Italia and majority interest in Sky Deutschland to create a European TV giant in a deal worth nearly $11 billion.