Mark Zuckerberg’s net worth passed $100 billion for the first time Thursday after Facebook hit a record high on optimism about the release of its TikTok competitor Reels. The 36-year-old joins fellow tech titans Jeff Bezos and Bill Gates as the only people in the world who currently have centibillionaire status, according to the Bloomberg Billionaires Index. Mr Zuckerberg’s fortune is largely derived from his 13 per cent stake in Facebook. The founders of America’s largest technology companies have enjoyed a mind-boggling accumulation of wealth this year as the coronavirus pandemic drives more people online, despite the US economy contracting at its fastest pace on record. Mr Zuckerberg has gained about $22bn this year, while Bezos is up more than $75bn. The staggering numbers have put Big Tech under increased scrutiny, with Mr Zuckerberg, Mr Bezos, Apple chief executive Tim Cook and Alphabet head Sundar Pichai testifying before Congress last month to defend allegations that their power and influence are out of control. The five largest American tech companies -- Apple, Amazon.com, Alphabet, Facebook, and Microsoft-- currently have market valuations equivalent to about 30 per cent of US gross domestic product, nearly double what they were at the end of 2018. US Senator Bernie Sanders, meanwhile, plans to introduce legislation to tax what he called “obscene wealth gains” during the coronavirus crisis. The “Make Billionaires Pay Act” would tax 60 per cent of the increase in the ultra-wealthy’s net worth from March 18 through the end of the year and use the revenue to cover out-of-pocket health-care expenses of all Americans. Mr Zuckerberg, who founded the social media giant from his Harvard University dorm room in 2004, has said he plans to give away 99 per cent of his Facebook shares over his lifetime. Even overseas, tech giants are among the top gainers this year. Tencent Holdings chief executive Pony Ma has added $17bn, taking his fortune to more than $55bn, while the wealth of Pinduoduo's Colin Huang has gained $13bn to $32bn. India’s Mukesh Ambani has become $22bn richer as the digital unit of his Reliance Industries got investments from firms including Facebook and Silver Lake. He’s now worth $80.3bn.