Tech IPOs are, at their core, giant liquidity events for founders. But Twitter is a little different, and it remains to be seen if that's a good thing or a bad thing.
Even though the company will instantly get a public value of up to $10 billion or more, none of the insiders can cash out right away. And only one of the top shareholders will become a billionaire—and he's no longer an employee of the company.
According to the company's S-1 filing with the Securities and Exchange Commission, the largest individual shareholder is Evan Williams, the company's former CEO. He has 12 percent of the company, or 56.9 million shares. He will become the only paper billionaire created by the IPO, with a paper net worth around $1.2 billion, if Twitter gets a valuation of just under $10 billion.
(Read more: No more secrets: Twitter IPO is now public)
Jack Dorsey, who is often the public face of Twitter, has a 4.9 percent stake, or 23.4 million shares, and could be worth around $470 million. By comparison, CEO Dick Costolo has around 7.5 million shares, giving him around $150 million, and venture capitalist Peter Fenton, who sits on Twitter's board, has a 6.7 percent stake, or 31.6 million shares, worth about $630 million.