SAN FRANCISCO (NYTIMES, BLOOMBERG) – In a rare change to Facebook’s top ranks, Mr Mike Schroepfer, chief technology officer and a long-time executive, plans to step down from his position next year, the company said on Wednesday (Sept 22).

Mr Schroepfer, 46, who has worked at Facebook for more than 13 years, plans to transition into a newly created role as a senior fellow, which he said would allow him to focus on activities outside the company. He said he would spend more time with family and on personal philanthropic efforts while continuing to recruit and develop technical talent for Facebook.

“This is a difficult decision because of how much I love Facebook and how excited I am about the future we are building together,” Mr Schroepfer said in a post on his personal Facebook page.

Apart from the departures of several top executives in 2018, chief executive Mark Zuckerberg has kept a tight circle of lieutenants around him for years. Chief operating officer Sheryl Sandberg has held her position since 2008.

Mr Schroepfer’s departure was announced as Facebook faces intense scrutiny for issues as varied as toxic speech, misinformation and privacy. The chief technology officer, who has overseen the building of artificial intelligence systems to identify and prevent violent and hateful posts from being seen on the social network, has been key to some of its efforts to battle the problems.

“He has played a critical role in almost everything we’ve done,” Mr Zuckerberg said on Wednesday in a company blog post.

Some former employees said they were concerned about Mr Schroepfer’s departure because he was widely viewed as one of the better-liked and approachable executives. He was also seen as a voice of reason as Facebook navigated crises.

“After I left FB earlier this month, many existing employees asked me who could now best be their ally on matters of societal import,” Mr Samidh Chakrabarti, who led efforts to crack down on harmful content on Facebook, wrote on Twitter on Wednesday. “Who was on my short list every single time? Schrep. So this is indeed significant.”

Mr Schroepfer joined Facebook in 2008 and has been chief technology officer since 2013, reporting to Mr Zuckerberg. He sits atop many of Facebook’s most ambitious organisations – including groups that the social network is depending on for future growth – such as engineering, infrastructure, augmented reality and virtual reality, and the blockchain and finance unit. His desk sits next to Mr Zuckerberg’s and Ms Sandberg’s at Facebook headquarters.

Mr Schroepfer’s most central role may be his oversight of Facebook’s AI organisation, which he helped build. That group develops the technology Facebook uses to automatically find and remove content that violates its policies, like nudity, hate speech and graphic violence. Pressure to improve those systems increased last week following a series of reports in the Wall Street Journal that found evidence describing the company’s struggles to reckon with issues like Covid-19 misinformation and human trafficking.

With billions of global users to serve, Facebook executives have pointed to AI technology as the best way to police posts at such a large scale. The technology is far from perfect, and Facebook also uses thousands of human content moderators to monitor posts on its apps.