In five years’ time, cable pioneer John Hendricks has assembled a subscriber base of more than 10.5 million for CuriosityStream, the niche factual programming streaming service that has been successful in getting picked up by cable operators in the U.S. and abroad.

Hendricks, the founder of Discovery Channel, and CuriosityStream president-CEO Clint Stinchcomb, disclosed the subscriber milestone on Tuesday as the company prepares to launch service in nine Latin American countries.

The independent media company’s biggest growth driver has been going the old-fashioned route of setting deals with cable operators such as Altice USA and Suddenlink. CuriosityStream gives operators broad on-demand rights to a range of nature, science, arts, history, documentary and travel-focused programming — including linear channel feeds in some cases — in exchange for a flat annual fee. The company’s raft of programming has also been popular in short-form bites on mobile platforms outside the U.S.

“It’s a path to reaching hundreds of millions of households worldwide,” Hendricks said. A slight majority of subscribers come from outside the U.S., Stinchcomb said.

CuriosityStream also has paying customers that subscribe directly, with the basic plan starting at $3 a month, or $19.99 a year. But more than direct-to consumer action, the cable bundling strategy is the largest component of the 10.5 million subscribers, Stinchcomb said. CuriosityStream’s partners include StarHub in Singapore, Totalplay in Mexico, Airtel in India, Multichoice’s DStv across Africa and Liberty Global / FLOW in the Caribbean, among other markets.

Stinchcomb said another growing source of subscriptions is universities, for libraries and research facilities, and corporate clients who give free subscriptions to the service to employees as a benefit perk.

Hendricks and his team went on a programming shopping spree in early 2015 to lock up long-term rights to some of the world’s most high-end and evergreen factual and documentary programming. The Curiosity Studios arm has also produced about 900 hours of original content to date and counting. Hendricks has deep relationships in the unscripted and documentary production community thanks to his groundbreaking tenure at Discovery Channel, which debuted in 1985.

CuriosityStream is in the process of translating its programming into Russian, Serbian, Spanish, Portuguese, Mandarin and Cantonese as it prepares to expand. The company’s growth begs the question of whether niche streaming platforms can survive the onslaught of big-league competition unleashed from Disney, WarnerMedia, Comcast and Apple. But it is telling that the biggest lift came from cable operators looking for on-demand content.

“We’re really the only pure factual subscription video on demand service out there today,” Stinchcomb said. “We’re not reality television or comedies. We’re not trying to be anything that we’re not. There is tremendous global appeal for factual content.”