AI Giving Compared: OpenAI’s 26% Stake, Anthropic’s 5% Fund

Anthropic said on 18 October 2026 that it is committing 5% of its shares to a new Anthropic Public Benefit Fund, and the next morning Elon Musk wrote that he will give one of his SpaceX shares to every child in America. Set beside OpenAI’s own published structure, in which the OpenAI Foundation holds a 26% stake in OpenAI Group, that makes three different ways of moving equity toward the public good.

We put the three side by side from each company’s own text: how much equity, through what vehicle, with what control rights, and who decides how the money is spent. Values are each source’s own figures; anything we calculated is labelled as our arithmetic.

Business Pill · MATCHING FUNDS

A short explainer on matching funds, where one party’s money is matched by another’s. Anthropic runs an employee equity donation match; the video teaches the general idea only and says nothing about any company in this story.

Three Commitments, Side by Side

What Was Posted on X

Anthropic’s own post announcing the Public Benefit Fund: 5% of shares to start, up to 2% more for every 50% rise in value over a baseline at the board’s discretion, and roughly 20% of shares committed to the public good once co-founder and employee pledges are counted. It is the primary source for the Anthropic row in our table.

Musk’s reply to Anthropic’s post, on 18 October: he recommends giving the shares directly to the public. As we read it, this is the design choice that separates his pledge from both labs’ structures.

Musk’s own pledge, posted on the morning of 19 October: one of his SpaceX shares to every kid in America next year, ‘the first of many’. The share counts and the roughly $10.5 billion value in our table are CNBC’s, not Musk’s.

Bloomberg’s post framing Musk’s pledge as coming after Anthropic said it would set aside a portion of its shares for the public benefit. We cite it for that framing only.

Axios’s post on how the AI boom could reshape global philanthropy, published the morning after Anthropic’s announcement. Axios puts Anthropic’s 5% at $100 billion if the company reaches a $2 trillion IPO value and frames the Anthropic and OpenAI vehicles as the world’s largest charitable organizations in the making; those are Axios’s figures and framing, which our 19 October update cites.

CNBC’s post on the pledge, citing an August SEC filing for Musk’s roughly 4.8 billion SpaceX shares, 6.4 billion with unvested awards and options, a 48.4% beneficial stake. We checked those counts against the filing itself in the 19 October update above.

Reuters’ post on X on 20 October, which sets Anthropic’s 5% fund and Musk’s one-share-per-child pledge side by side as ‘sharply different blueprints’ for sharing the spoils of the AI boom and links to Reuters’ 19 October report. Reuters’ value estimates for each pledge, from that report, are in the 20 October update.

President Donald Trump’s post on X at 21:24 UTC on 19 October, thanking Musk for giving SpaceX stock to millions of American children “through TRUMP ACCOUNTS”. This piece uses it only for that line; the post does not describe how the shares would be held or whether a lockup would apply.

Anthropic: A Fund That Grows With the Valuation

Anthropic wrote that “Subject to stockholder approval, 5% of Anthropic’s shares will be committed today, with an additional 2% added at the board’s discretion for every 50% increase in the company’s value above a set baseline.” The FT put those shares at “around $48bn at its latest valuation”, describing Anthropic as “The $965bn start-up”.

The company said it set the Fund up “as a wholly-owned LLC—rather than a 501(c)(3) or other format—to give adjustability between different forms of giving”, and that “None of the Anthropic equity held by the LLC will be used for lobbying or political giving, in the US or abroad.”

Anthropic also wrote that its co-founders “pledged to donate 80% of their equity holdings”, that about half its employees take part in an equity donation match, and that “When combined with today’s announcement, roughly 20% of Anthropic shares will be dedicated to the public good”.

Board seats run through separate share classes. Anthropic’s Long-Term Benefit Trust holds a class of stock, Class T, that “grants the Trust the authority to elect and remove a number of Anthropic’s board members”. CNBC, reporting Reuters’ read of the IPO filing on 29 September, wrote that “Anthropic’s remaining four board directors will be elected by another oversight body, the startup’s Long-Term Benefit Trust.” The same report said a single Class F share directed by the co-founders “amounts to 50.1% of the total voting power over key corporate matters”.

OpenAI: A Foundation That Holds the Control

OpenAI’s structure page states that “As of the closing of the recapitalization, the OpenAI Foundation holds a 26% equity stake in OpenAI Group, worth approximately $130B based on OpenAI Group’s current valuation.” The page says the structure was “announced on October 28, 2025”.

It has its own escalator: “If OpenAI Group’s share price increases greater than tenfold after 15 years, the OpenAI Foundation will receive significant additional equity.” The page also states that “the OpenAI Foundation appoints all members of the board of directors of OpenAI Group and can replace directors at any time.”

OpenAI wrote that the Foundation “will initially focus on a $25B commitment across two areas”: health and curing diseases, and technical solutions to AI resilience.

Musk: Shares Handed Out Directly

Musk replied to Anthropic’s announcement on 18 October: “I recommend giving the shares directly to the public”. The next morning he wrote: “Next year, I will give one of my SpaceX shares to every kid in America. This will be the first of many.” Bloomberg described the pledge as coming “after competitor Anthropic PBC said it would set aside a portion of its shares for the public benefit”.

CNBC reported that “Musk currently owns about 4.8 billion SpaceX shares, according to an August SEC filing”. It added that “There were 72 million children under 18 in the U.S. as of July 1, 2025, according to official census data”.

On those numbers, CNBC wrote, the gift would amount to “about $10.5 billion worth of shares” at Friday’s closing price of $146.03.

By our arithmetic on CNBC’s figures, 72 million shares is about 1.5% of the about 4.8 billion SpaceX shares CNBC says Musk currently owns.

The Structural Reading

As we read it, both labs tie their public-good stake to their own valuation: Anthropic’s Fund can add 2% for every 50% rise above a baseline, and OpenAI’s Foundation holds a warrant tied to a tenfold share-price rise. The more the company is worth, the more of it is pledged.

As we read it, the difference is where control is written down. At OpenAI the Foundation that holds the 26% also appoints the board; at Anthropic the Fund’s governance is not yet published, the Long-Term Benefit Trust elects some directors through Class T stock, and CNBC reported a founders’ Class F share with 50.1% of voting power on key matters. Musk’s posts describe handing shares to individuals and do not describe any governance role.

As we read it, the timing is uneven: OpenAI’s structure was announced on 28 October 2025, while Anthropic’s Fund and Musk’s pledge came within a day of each other, and Bloomberg framed the pledge as coming after Anthropic’s announcement.

Update, 19 October: Axios on What AI Equity Means for Philanthropy

Axios reported on 19 October that the IPOs of Anthropic and OpenAI “will create the world’s largest charitable organizations,” shifting the center of gravity of global philanthropy to Silicon Valley. Axios put Anthropic’s pledge at $100 billion “if it reaches a value of $2 trillion in its IPO”; that is Axios’s calculation on a valuation that has not been set, not a figure from the company.

Axios also reported that Anthropic cited AI’s effects on the labor market as one potential use of the fund, said it has already committed $200 million to studying and addressing that issue, and said “bolder approaches may be needed.” Axios noted that Anthropic has not specified what those approaches would be, or whether the fund would make direct payments to workers affected by AI. Axios’s description of OpenAI matches our table: a nonprofit foundation holding a 26% equity stake worth about $130 billion, with the power to appoint OpenAI’s board.

Axios added that Anthropic’s founders and some employees have close ties to effective altruism, a movement it said has come under sharp criticism from the Trump White House, and that former White House official Taylor Budowich highlighted on X a 2010 comment by Anthropic CEO Dario Amodei about how to weigh deaths in charitable giving.

As we read it, Axios’s framing turns the comparison in our table into a ranking by size, but those sizes depend on IPO valuations that have not been set, while the difference that is already fixed is who controls the payouts.

Update, 19 October: One Share per Child Is About 1.5% of the SpaceX Shares Musk Holds

We checked CNBC’s figures against the filings. In a Schedule 13G signed on 13 August 2026, Musk reported beneficial ownership of 6,418,547,515 SpaceX shares, or 48.4%. The filing breaks that down into 849,494,440 Class A shares and 3,916,980,790 Class B shares held by trusts where he is trustee, 1,302,072,285 restricted Class B shares whose vesting “is subject to the satisfaction of certain performance and other conditions”, and 350,000,000 Class B shares issuable on exercise of options.

By our arithmetic, the trust holdings add up to 4,766,475,230 shares, which matches CNBC’s “about 4.8 billion”. The US Census Bureau’s Vintage 2025 estimates put the population aged 0 to 17 at 72,021,348 on 1 July 2025, summed by us from its single-year figures. One share per child would therefore be about 1.5% of the shares Musk holds through the trusts and about 1.1% of his full beneficial stake. At the $146.03 Friday close CNBC cited, that is about $10.5 billion, the same as CNBC’s figure.

Measured against the whole company, SpaceX’s 10-Q reported 7,696,293,669 Class A and 5,485,486,276 Class B shares outstanding as of 28 July 2026. By our arithmetic, 72 million shares is about 0.55% of that total. The basis is different from Anthropic’s 5%: Anthropic’s Fund is a commitment of the company’s own shares, while Musk’s pledge is a gift from his personal holding, so the two percentages are not a like-for-like comparison.

The filing also says each Class B share, which carries 10 votes, “will convert automatically into one share of Class A Common Stock upon any sale or certain transfers”, subject to certain exceptions. Musk has not said which class of shares he would give, and the filing does not say whether a gift to minors would trigger that conversion.

Later on 19 October, Bloomberg reported that Musk has agreed in principle to distribute the stock through the Trump Accounts initiative, according to a person familiar with the matter; Musk did not specify how he intends to make the donation and did not immediately respond to Bloomberg’s request for comment. The initiative, created under last year’s tax and spending bill, provides $1,000 to American children born between 2025 and 2028, Bloomberg wrote.

Trump then thanked Musk in a Truth Social post for “his incredible generosity in giving SpaceX Stock to millions of American children through TRUMP ACCOUNTS,” adding that “this is exactly what was envisioned when we created TRUMP ACCOUNTS” (text as archived by trumpstruth.org; relayed by FirstSquawk at 20:46 UTC).

Update, 20 October: How Reuters Frames Anthropic vs Musk

Reuters set the two pledges side by side. In a post on X on 20 October promoting its 19 October report, it said Anthropic and Musk “have laid out sharply different blueprints for sharing some of the spoils of the AI boom, a split that may shape how the technology’s financial windfall reaches the public.” The report itself, read in full via a syndicated copy, describes Musk as “arguing for such direct distributions as leading AI companies face growing public scrutiny.”

Reuters also put its own values on each side. For Anthropic, it said a market debut at roughly $2 trillion, or the lower valuation of around $1.5 trillion that it reported some investors are weighing, would value the 5% stake in a range of $75 billion to $100 billion. For Musk, it used census figures of 72 million children and a price of $149 a share to reach a total “worth over $10.7 billion”. That price is higher than the $146.03 close used in the update above, which is why the two totals differ.

On how Musk’s pledge would work, Reuters reported that “it was not immediately clear how Musk’s donations would work, whether they would be linked to Trump Accounts and whether there would be any kind of lockup period for the shares,” and that SpaceX did not immediately respond to a request for more details. It noted that SpaceX President Gwynne Shotwell and her husband pledged earlier this year a share of their SpaceX stock to each of more than two million children under the Trump Accounts initiative.

President Donald Trump named a vehicle. In a post on X on 19 October, he thanked Musk for “giving SpaceX Stock to millions of American children through TRUMP ACCOUNTS” and wrote that “this is exactly what was envisioned when we created TRUMP ACCOUNTS.” The post does not say how the shares would be held or whether any lockup would apply, and the Musk post quoted in this piece does not mention Trump Accounts.

Update, 20 October: Gerstner Wants Trump Accounts Open to Anyone Under 40

Trump Accounts may be opened to a far wider age group. Brad Gerstner, the Altimeter Capital CEO whom the New York Post calls “the architect of Trump Accounts,” is working to expand the accounts’ remit “to make it accessible to anyone under 40,” according to a New York Post column by Lydia Moynihan published on 19 October. The column says the updated legislation “could come within months” and would also seek to make funding permanent. Right now, it says, the accounts are only for citizens under 18.

Gerstner told the Post that Musk’s donation is just “the tip of the iceberg,” and he estimates private contributions to Trump Accounts could total $100 billion by the end of 2027. The column does not say whether the SpaceX shares Musk pledged to children would also go to new accountholders over 18, and no bill text is cited.

The Structural Read

As we read it, Anthropic and OpenAI have both written an escalator into the commitment: Anthropic’s Fund can add 2% for every 50% rise in value above a baseline, and OpenAI’s Foundation holds a warrant tied to a tenfold share-price rise after 15 years.

As we read it, OpenAI’s page joins equity and board control in one body, the Foundation, while Anthropic splits them: the Fund holds shares, the Long-Term Benefit Trust elects some directors through Class T stock, and the Fund’s own governance is still to be published.

As we read it, Musk’s posts describe a different instrument altogether: shares given to individuals, with no fund, trust or board role described.

Three Implications

INVESTORS IN A LISTING Anthropic says the 5% is subject to stockholder approval and that more can be added at the board’s discretion; the valuation baseline has not been published.

CHARITIES AND RECIPIENTS OpenAI wrote that its Foundation will initially focus on a $25B commitment; Anthropic named large donations to nonprofits or direct distributions to specific populations as examples.

RIVAL LABS Bloomberg framed Musk’s pledge as coming after Anthropic’s announcement.

The Business Engineer Lens

This story maps onto the Business Engineer framework Inside Anthropic’s Permission Layer.

The analysis argues of Anthropic: “It is becoming the first major AI lab actively attempting to define the governance layer of the AI stack.”

As we read it, the Public Benefit Fund and the Class T Trust are governance written into the cap table. The analysis was published in June 2026 and does not discuss the Fund, OpenAI’s Foundation or Musk’s pledge.

What Is Not Established

Anthropic has not published the valuation baseline or the Fund’s governance; it wrote that it “will share more about the Anthropic Public Benefit Fund’s structure and governance, including the valuation milestones” in the coming months. Musk has not said how the shares would be distributed or held for minors, and CNBC wrote that it had “reached out to SpaceX for further comment”. The dollar values in the table come from three different sources on three different bases and are not a like-for-like comparison.

The Bottom Line

Anthropic committed 5% of its shares to a public benefit fund on 18 October 2026, subject to stockholder approval, with up to 2% more for every 50% rise in value above a baseline; the FT valued the 5% at about $48bn. OpenAI’s Foundation holds a 26% stake in OpenAI Group that OpenAI says is worth about $130B, and it appoints the Group’s board. Musk wrote that he will give one SpaceX share to every child in America next year, which CNBC valued at about $10.5 billion.