As artificial intelligence giants Anthropic and OpenAI move toward public listings, the dominant question in Silicon Valley is which investors stand to reap the largest rewards. The answer, it turns out, is nearly all of them.
At least 95 investors have placed bets on both Anthropic and OpenAI, according to data from PitchBook, which tracks private-market investment. Blue-chip venture firms such as Sequoia Capital, Founders Fund, Coatue Management, and Altimeter Capital Management hold stakes in both start-ups.
This strategy breaks sharply with historical precedent. Traditionally, venture capital firms avoided backing direct competitors in a nascent, fast-growing sector, viewing it as a conflict of interest. The AI boom, however, has upended nearly every norm in Silicon Valley, including how investors nurture start-ups. Top firms on Sand Hill Road—the Menlo Park, Calif., corridor that remains the epicenter of venture capital—have adapted their strategies to ensure they do not miss out on the companies that could become the next $2 trillion market leaders.
“Few large investment funds want to say, ‘We missed both’ OpenAI and Anthropic,” said Karan Mehandru, an investor at Madrona Venture Group.
The extent to which Silicon Valley’s fortunes are tied to these two privately held companies is evident in the sheer volume of capital they have amassed. Anthropic has raised more than $130 billion from roughly 300 investors, per PitchBook, including venture firms, hedge funds, big tech companies, and Middle Eastern sovereign wealth funds. OpenAI has secured more than $180 billion from approximately 230 investors, such as major tech corporations and Joshua Kushner’s Thrive Capital. By comparison, Facebook raised just $2.4 billion before its 2012 IPO, while Uber raised roughly $20 billion prior to its 2019 listing.
Not every investor on PitchBook’s shareholder lists acquired stakes through traditional funding rounds; some gained exposure indirectly via private share sales on the secondary market, purchasing stock from existing holders like employees or early backers.
Investor appetite has been further whetted by SpaceX’s successful $1.7 trillion initial public offering in June. Anthropic is now targeting a public offering this year that could value the company at $2 trillion, potentially marking the largest listing in history. OpenAI may follow next year with an offering of similar magnitude.
For investors, this dynamic means “all the numbers are bigger, including the entry price and the exit price,” said Sohail Prasad, chief executive of Destiny100, a firm that acquired shares of both OpenAI and Anthropic on the secondary market.
Anthropic and OpenAI declined to comment. (The New York Times has sued OpenAI and Microsoft, alleging copyright infringement related to AI training data; both companies have denied the claims.)
For years, venture investors adhered to a familiar playbook: take a significant stake in a young company, secure a board seat, and provide hands-on guidance. When Facebook went public, Accel Partners held an 11.4% stake, and partner Jim Breyer sat on the board alongside venture luminaries Marc Andreessen and Peter Thiel. When Uber listed, Benchmark Capital held 11%, with partner Matt Cohler on the board.
Anthropic, founded five years ago, has followed a markedly different trajectory. Early on, venture firms largely dismissed the start-up as a science project; more than 20 firms rejected its pitch, according to Anthropic investor Anjney Midha. Initial backing came instead from effective altruism circles—a philanthropic movement prioritizing data-driven social impact.
Spark Capital eventually led a 2023 funding round, with investor Yasmin Razavi joining Anthropic’s board. Around that time, Anthropic executives courted Guy Oseary, a Hollywood talent manager who invests via Sound Ventures. Though impressed, Oseary faced a conflict: Sound Ventures had already backed OpenAI. After securing permission from both Sam Altman of OpenAI and Anthropic’s Dario Amodei, Sound Ventures became one of the first firms to invest in both rivals, subsequently raising a dedicated AI fund.
As capital requirements outgrew the capacity of traditional venture funds, firms engineered new structures. In 2024, Menlo Ventures created a “special purpose vehicle” to pool $750 million for a follow-on Anthropic investment. Thrive Capital deployed a similar vehicle for OpenAI.
Tech giants Google, Amazon, Microsoft, and Nvidia have also taken stakes in both start-ups, often pairing equity with lucrative cloud computing and chip supply contracts. Several now rank among the companies’ largest shareholders.
Lightspeed Venture Partners and Iconiq Capital later led Anthropic rounds. Menlo, Lightspeed, and Iconiq now own 1% to 2% of Anthropic, placing them among the largest outside investors, according to people familiar with the stakes. (Menlo and Lightspeed do not hold OpenAI stakes; Iconiq holds a small position.)
While venture firms typically target ownership above 1% or 2%, a potential $2 trillion valuation for Anthropic promises an enormous windfall even at those levels. Ms. Razavi of Spark Capital remains the sole investor with a board seat at Anthropic.
After Anthropic’s coding and automation tools gained traction last year, investing in the company became “consensus”—venture parlance for an obvious, industry-wide winner. Global investors clamored for shares despite limited access to detailed performance data or board representation.
Sequoia Capital had previously passed on Anthropic, partly due to its backing of Elon Musk’s rival xAI and its significant OpenAI position. However, this year Sequoia participated in two Anthropic financing rounds, including co-leading a May round that valued the company at $900 billion.
Other firms gained exposure through acquisition-driven stock swaps. Anthropic has acquired at least four companies and OpenAI roughly a dozen, per PitchBook. Madrona received OpenAI shares last year after the startup acquired Statsig, an AI software provider, for $1.1 billion; Madrona’s Statsig holdings converted into OpenAI stock. “If it had been stock from someone else, maybe the answer would have been different,” Mr. Mehandru said of the swap.
In February, Madrona similarly obtained Anthropic shares when the startup acquired Vercept, a developer of computer-operating agents, in which Madrona was an investor.
