Ev Williams is finally moving on from Twitter

It’s been a long time since Ev Williams, one of Twitter’s four co-founders and its one-time CEO, was making any notable decisions within the company he created way back in 2006.

But on Friday, when Williams announced that he is leaving Twitter’s board to “ride off into the sunset” and “focus on some other things,” it still felt like the end of an era. Williams, always thought to be a bit of a counter-balance (and a former rival) to CEO Jack Dorsey, is officially out the door.

“I’m very lucky to have served on the @Twitter board for 12 years (ever since there was a board). It’s been overwhelmingly interesting, educational — and, at times, challenging,” Williams tweeted Friday.

Williams and Dorsey have historically been rivals, battling for power and influence internally while taking turns at the helm of Twitter in the company’s early days. Dorsey was Twitter’s first CEO, but was a bad manager and was quickly replaced by Williams in 2008. Dorsey was essentially booted from the company. When Williams was later replaced by Dick Costolo in 2011, Dorsey returned as Twitter’s executive chair with a vengeance.

Here’s how we reported the transition in a Recode story from 2015:

[Dorsey] seems to be a completely different man than the one who returned to Twitter in March 2011 as executive chairman and product czar. Former colleagues recall a man looking for payback for his 2008 ouster; loyalty was key, and many who were loyal to Twitter’s other co-founder, Ev Williams, were booted from the company.

Even though Williams said publicly that bringing Dorsey back as CEO in 2015 was the right move, his seat on the board always felt … interesting. Dorsey tweeted Friday that he would “miss [Ev’s] voice in our board conversations.”

As a board member, Williams has been a thoughtful Twitter critic. Two years ago, he said that the advertising business that supports digital media is a “broken system” — a not-necessarily-untrue yet interesting thing to say when you sit on the board of a company that makes its money through advertising.

He openly contemplated whether or not Twitter helped get Donald Trump elected president, and apologized if it did. Most recently, he questioned Twitter’s decision to track follower counts, calling it “unhealthy.”

Which is all to say that while Williams hasn’t necessarily been calling the shots for Twitter, he’s still been a vocal presence made all the more interesting by the fact that he had a vote on the board. Almost 13 years after Twitter’s founding, that vocal co-founder is ready to move on. (Of course, Williams already runs another company, the publishing business Medium.)

“I’m going to ride off into the sunset (or…down Market Street), so I can focus on some other things,” he tweeted. “I will always be rooting for the team (and, if someone lets me in, come by for lunch).”