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- As Reddit prepares to go public, a new filing with the SEC has revealed its biggest backers.
- OpenAI's Sam Altman is the third-largest shareholder, the filing revealed.
- It was previously known he was a Reddit investor — but not to this extent.
We learned a new detail about Sam Altman Thursday: just how much he supports Reddit.
In preparation for its highly-anticipated IPO, the online social forum filed an S-1 form with the Securities and Exchange Commission on Thursday, detailing the company's financial background. The filing revealed that Altman, the CEO of OpenAI, owns an 8.7% stake in the company.