• AT&T CEO John Stankey spoke at UBS' global TMT conference Tuesday.
• He said activated HBO Max subscribers have reached 12.6 million.
• Stankey defended AT&T's decision to release WarnerMedia's 2021 slate of movies on HBO Max at the same time they hit theaters but said the company could "readjust" post-pandemic.

AT&T's WarnerMedia added 4 million HBO Max signups since the end of the third quarter, chief executive John Stankey said Tuesday.

HBO Max now has 12.6 million activated users, up from 8.6 million on Sept. 30, Stankey said during UBS' Global TMT conference. Stankey credited new original content, such as "The Undoing," for the surge in subscribers.

Stankey and WarnerMedia CEO Jason Kilar are aggressively stocking HBO Max with new content in an effort to get to 50 million U.S. subscribers, the streaming service's 2025 goal. By comparison, Disney+ in November blew past expectations for its first year with 73.7 million subscribers.

The company shocked Hollywood last week with its decision to release its entire 2021 slate of movies, 17 in all, on HBO Max the same day as their theatrical release. Stankey reiterated the decision was made with customers in mind but also said AT&T would "adjust and work the model differently" if people return to theaters in droves when the pandemic ends.

"We were going to be in a situation where the psyche of the population and willingness to go back into theaters, that's going to be a prolonged recovery," said Stankey. "The question is what's best to deal with that — it's a win-win-win situation — a win for us, win for customers, win for partners."

Director Christopher Nolan, who has made movies exclusively for Warner Bros. for nearly 20 years, harshly criticized Stankey's decision to break the decades-long theatrical window Monday.

"Some of our industry's biggest filmmakers and most important movie stars went to bed the night before thinking they were working for the greatest movie studio and woke up to find out they were working for the worst streaming service," Nolan said Monday in a statement to The Hollywood Reporter.

"Warner Bros. had an incredible machine for getting a filmmaker's work out everywhere, both in theaters and in the home, and they are dismantling it as we speak," Nolan said. "They don't even understand what they're losing. Their decision makes no economic sense, and even the most casual Wall Street investor can see the difference between disruption and dysfunction."

Stankey has reorganized WarnerMedia over the past two years to refocus the company around streaming video. He said while live news and sports won't initially be part of HBO Max, that decision could change when HBO Max subscribers roughly equal the number of traditional pay-TV households. Stankey said earlier this year he expects the number of pay-TV households to fall to about 55 million or 60 million in the coming years.

Both former and current WarnerMedia executives have been skeptical of some of the decisions Stankey has made regarding the rollout of HBO Max, CNBC reported last week. AT&T shares are trading near a 10-year low.

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