Mentioned on page 206, "The Perils and Opportunities of Artificial Intelligence" of the book.

https://c2pa.org/ seems to be the latest iteration of it.

> What is the Coalition for Content Provenance and Authenticity (C2PA)?

> The C2PA is a Joint Development Foundation project to collectively build an end-to-end open technical standard to provide publishers, creators, and consumers with opt-in, flexible ways to understand the authenticity and provenance of different types of media. C2PA opposes efforts to make content provenance measures mandatory.