OpenAI started as a nonprofit and became a corporation. Anthropic started as a corporation and is building a philanthropic arm.
The real question may be less about the entity type, or even how much they pledge, and more about who gets to define the public good.
https://www.bloomberg.com/news/articles/2026-10-18/anthropic-plans-to-shift-some-shares-into-new-public-good-fund
Bloomberg.comAnthropic Plans to Shift Some Shares Into New ‘Public Good’ FundAnthropic PBC said it plans to put 5% of its shares into a new so-called public benefit fund that allows it to make donations that can address “the public good,” including mitigating AI’s impact on the job market.