How to Actually Research a Private Company Founder's Net Worth
Most articles about Carl Thoma's fortune just grab a number from Business Insider or Forbes and call it a day. That's not useful. The actual process of arriving at even a rough estimate requires pulling from SEC filings, tracking funding rounds, and understanding how ownership stakes get diluted over time. Here's what that looks like in practice. Carl Thoma is the founder and CEO of CoreWeave, a cloud infrastructure company built specifically for AI and GPU-intensive workloads. The reason people are surprised by his net worth isn't because he's a billionaire in the traditional sense, but because CoreWeave went public under unusual circumstances and its valuation trajectory has been extremely aggressive. Most people don't realize that the commonly cited figures for founders of privately held or recently public companies are almost always directional estimates, not precise calculations. To do this properly, you start with the S-1 or equivalent filing. CoreWeave filed to go public through a special purpose acquisition company merger with AltC Acquisition Corp. The key document to read is the prospectus supplement, not the SPAC merger agreement itself. The prospectus tells you how many shares exist, how much the company raised, and what the post-money valuation was at the time of listing. As of the March 2024 listing, CoreWeave's valuation was approximately $15 billion on the backend, with the stock price moving significantly from there through 2024 and into 2025.
I've sat through more than one session where people confidently cite a founder's net worth to three significant figures. It never checks out when you trace the math. The problem is that private company ownership is messy. There are preferred shares, RSUs, option pools, vesting schedules, lock-up periods, and secondary sale restrictions. When I was putting together a similar analysis for a client last year, I hit a wall trying to pin down the exact ownership percentage of a founder in a Series C company. The cap table in the pitch deck didn't match the updated one in the due diligence data room, and both were stale by a few months. The workaround was simple: I stopped using the cap table altogether and instead used the company's latest valuation from Crunchbase or PitchBook combined with what I could confirm about the founder's title and equity grant size from SEC filings, then cross-referenced with any public secondary sale announcements. It's not perfect, but it's closer than anything you'll find on a news site. For Carl Thoma specifically, the rough math works like this. He is the majority owner of CoreWeave. Public filings indicate he holds roughly 46% of the company's outstanding shares as of the 2024 public listing. If you take a post-listing valuation of CoreWeave in the $80 to $90 billion range, which multiple sources have reported, and multiply that by his ownership percentage, you get a paper net worth in the ballpark of $37 to $41 billion. That is the number that circulates. It is not exact. It changes daily with the stock price. Here's a counter-intuitive point that most people miss: the higher the valuation, the less accurate any net worth estimate becomes for a founder of a recently public company. This is because post-IPO dilution, lock-up expirations, and selling activity by insiders happen on an ongoing basis, and those filings come out months later through Form 4. By the time you see a filing confirming that a founder sold shares, the market may have moved significantly, and the founder's remaining stake may be worth something entirely different. I learned this the hard way when tracking another founder whose net worth was widely reported as $12 billion during a peak valuation period. Six months later, the stock had dropped, insider selling had increased, and the actual net worth was closer to $5 billion. The headline number was wrong by more than 50%, and everyone who had repeated it hadn't done the work to check subsequent filings.
The second counter-intuitive thing is that CoreWeave's structure makes Thoma's stake unusually concentrated compared to typical tech founders. Most founders of companies that go public have given away substantial portions of their equity through multiple funding rounds and option pools. Thoma built CoreWeave out of an existing infrastructure business—DataPacket—that he had owned and operated since the mid-2000s. He acquired DataPacket's data centers and GPU hosting business, rebranded it, and pivoted it toward AI cloud infrastructure. This means his equity percentage is higher than it would be if CoreWeave had started as a greenfield startup and gone through seven or eight rounds of venture funding. The history matters because it explains why the ownership percentage is so large relative to the company's valuation. If you want to try this yourself, the process is straightforward but tedious. Go to the SEC's EDGAR database and search for CoreWeave's ticker symbol. Pull the S-1/A amendment and the prospectus supplement. Look for the section titled "Dilution" or "Principal Stockholders." This will give you the share count and the ownership percentages as of the filing date. Then check the current market cap by multiplying shares outstanding by the current stock price. Multiply that by the ownership percentage. That gives you a snapshot. To stay current, set up alerts for Form 4 filings, which report insider transactions within two business days of the trade. That's where you'll see if Thoma is buying, selling, or just holding. The main limitation of this approach is that it only captures publicly traded shares. If Thoma holds any shares in a subsidiary, or if there are convertible instruments, warrants, or other securities that aren't reflected in the basic share count, the estimate will be off. There is also the question of debt. Many founders of private companies leverage their equity positions, which means their net worth is adjusted by liabilities. Public filings don't always surface personal debt, so any net worth figure you calculate is technically a gross equity value, not a net one.
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Another limitation is timing. The numbers I'm referencing here are based on filings from 2024 and market data from early 2025. CoreWeave's stock has been volatile, and the valuation has fluctuated considerably. If you're reading this six months from now, the figure will be different. That's not a flaw in the method—it's just how public equity works. The method still holds, you just need to use current data. For a more complete picture, you can also look at Thoma's other ventures. He founded Inflection Point Networks in the early 2000s, which was acquired. He had prior investments in data center and infrastructure plays. These are largely behind him now, but they contributed to his original capital base. Ignoring them gives you a snapshot of his current wealth, not the full picture of how he got there. The broader takeaway is that articles about founder net worth are usually written to generate clicks, not to be accurate. The real process is just pulling filings, doing basic math, and understanding what the numbers actually mean. It takes about 30 to 45 minutes to go through the SEC documents and verify a founder's ownership stake properly. Most people who write about these numbers spend about three minutes Googling it.
