Founded by Oscar-winning “Man on Wire” producer Simon Chinn and Emmy winner Jonathan Chinn, high-end documentary producer Lightbox is navigating the next phase of its evolution, and exiting one of the key initiatives that helped the transatlantic company set up shop.

Variety can reveal that the London- and Los Angeles-based outfit is buying back its shares and leaving U.K. broadcaster Channel 4’s Indie Growth Fund (IGF), which invests in British production companies by taking minority stakes to help them grow. Lightbox is now fully independent, and plans to remain so “for the short term” before considering a sale in the future.

Since accepting the Channel 4 investment in 2014, the “Whitney” producer has more than tripled in size, growing from a £4-million to £13-million turnover company, and establishing itself as a bona fide U.S.-U.K. player specializing in high-end documentaries for streaming services and premium cablers.

“It’s helpful to think of two phases of our evolution,” says Simon Chinn, who notes that Lightbox 2.0 has “outgrown” the Channel 4 backing, which was useful in “holding [their] feet to the fire” as a hungry start-up, but has become less congruous with the company’s strategy in recent years, particularly as Lightbox produces limited work for Britain’s terrestrial broadcasters to begin with.

“[At the time], there was a thought that maybe we could develop a relationship with Channel Four outside of the investment, just in terms of content creation. And it turned out that we took our business in a slightly different direction, and focused more on international and U.S. content,” adds Jonathan Chinn.

Regardless, the founding partners — who are cousins, with Simon based in London and Jonathan in Los Angeles — underline that they “feel nothing but positive” about the investment relationship with Channel 4, and that the split is “entirely amicable.”

Lightbox’s portfolio includes the Emmy Award-winning Nat Geo doc “LA 92”; the Grammy-nominated theatrical doc “Whitney,” which premiered at Cannes; Netflix’s “Tell Me Who I Am,” which premiered at Telluride and the London Film Festival; Hulu and BBC Two’s “Untouchable: the Fall and Rise of Harvey Weinstein,” which premiered at Sundance 2019; and theatrical Tina Turner documentary “Tina.”

More recent and forthcoming productions include “Hip Hop Uncovered” (FX), “Supervillain” (Showtime), “Return to the Moon” (National Geographic), “Sophie’s Story” (w/t, Netflix) “Diagnosis” (Netflix) and “Murder Mountain” (Netflix/Fusion).

While countless producers struggled to win commissions and stay afloat in 2020, Lightbox had its most profitable year to date, and didn’t need to lay off a single member of staff. The company sold a number of projects in that time, all of which are largely archival efforts, which can be pricey to compile but not as insurmountable in a pandemic as pulling off a scripted drama with hundreds of cast and crew.

“It does speak to the robustness of the premium marketplace among the streamers and premium U.S. cable buyers,” says Jonathan Chinn. “The companies that struggled more were the ones that face the U.K. broadcasters exclusively. Those kinds of production companies tend to make more observational films, and those productions were hard to sustain during that period. By contrast, a lot of the stuff that we do is past tense.”

One major archival effort set to launch next year — likely in Cannes — is a theatrical documentary on Princess Diana, helmed by “Tell Me Who I Am” director Ed Perkins and told solely through archival footage. After playing in cinemas, the film, for which Altitude is handling sales, will debut on HBO and Sky Documentaries in the U.K.

Simon Chinn acknowledges the “challenge” of another Diana project on the heels of the latest season of “The Crown” and the hot anticipated Kristen Stewart-fronted Pablo Larrain film “Spencer” — “Making a film about Diana that will feel distinctive is something that is very front of mind for us,” he admits — but the executive notes that public interest in the late monarch is bottomless.

Looking ahead, Lightbox will look to beef up its returnable series roster. While limited series contribute more to the company’s turnover than feature documentaries, Jonathan Chinn notes that returnability is key to scaling the business, albeit tricky to pull off in the premium space. Netflix didn’t renew the outfit’s medical series “Diagnosis,” but “we’re confident we’ll crack it this year,” he notes. Projects in the sports arena focused on specific athletes are a key area of interest.

The through-line for all Lightbox projects, however, is premium, and that bodes well given today’s marketplace for non-fiction. While the Chinns were among the first to play in the high-end documentary space, that level of quality fare is now seemingly the standard for all documentary content, and particularly for streamers such as Disney Plus (which includes Nat Geo as a tile), Netflix, Apple TV Plus and Amazon Prime Video.

“All the [streamers] now realize that if they’re going for a streaming audience that pays subscriptions, and they want to compete, they’re going to have to get a fair amount of premium content that’s going to get talked about and justify people’s subscription dollars, so it’s become a really open market in that sense,” explains Jonathan Chinn. “Because we were there early on in the premium evolution, we have a little bit of experience in how to navigate it.”