Salesforce said Wednesday that Bret Taylor will step down as co-CEO on Jan. 31, leaving Marc Benioff once again alone at the top of the cloud software company he co-founded in 1999.

Benioff had closely embraced Taylor, who joined the company in 2016, when he sold his producitivty software startup Quip to Salesforce. Taylor played a key role in Salesforce’s $27.1 billion acquisition of Slack, its largest transaction ever.

Before that, Taylor sold FriendFeed to Facebook parent Meta and helped to create Google Maps. Taylor played a key role in Salesforce’s bid to acquire Slack for $27.1 billion, its largest transaction to date. Many onlookers saw Taylor as the person who could one day take over for Benioff as the head of Salesforce.

Exactly one year ago, Salesforce promoted Taylor from his positions of president and chief operating officer to be co-CEO alongside Benioff. At that time, Benioff described Taylor as “a phenomenal industry leader who has been instrumental in creating incredible success for our customers and driving innovation throughout our company.”

Just two months ago, Benioff and Taylor were speaking together onstage at Salesforce’s customer conference Dreamforce in San Francisco. The duo each donned rabbit ears, a reference to the rabbit mascot for the Genie service Salesforce was introducing at the time.

The announcement comes almost three years after Keith Block, an Oracle executive, left as co-CEO of the company. In February 2020, Keith Block departed as co-CEO. Block had been the company’s operating chief before being promoted in 2018.

“I am grateful for six fantastic years at Salesforce,” Taylor said in a statement. “Marc was my mentor well before I joined Salesforce and the opportunity to partner with him to lead the most important software company in the world is career-defining. After a lot of reflection, I’ve decided to return to my entrepreneurial roots. Salesforce has never been more relevant to customers, and with its best-in-class management team and the company executing on all cylinders, now is the right time for me to step away.”

It’s been a busy year for Taylor, as he was chairman of Twitter heading into Elon Musk’s acquisition of the social networking company, a deal completed last month. In an interview in September, Taylor said that the deal “doesn’t come up a lot” in Salesforce customer meetings. Taylor hasn’t tweeted since Oct. 26.

Benioff told CNBC that he liked the idea of having someone share the CEO role so they could have a “divide and conquer strategy” and so he could spend time investing, doing philanthropy and mentoring other business leaders.

Taylor made $22.8 million in total compensation in fiscal 2022, mostly from stock awards, according to the company’s latest proxy filing. That’s up from $13.9 million the prior year. The median pay for a Salesforce employee in the past year was $181,612, the filing said.

As of Jan. 31, Taylor had roughly $80 million of unvested stock units. Most of that was from restricted stock he received when Salesforce purchased Quip. Those restricted shares “vest in equal quarterly installments through August 2023 subject to Mr. Taylor’s continued employment with the Company,” the proxy filing says.

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