C2PA (content provenance standard)
Japanese C2PA（コンテンツの来歴を示す標準）
C2PA is an open standard that attaches a signed record to digital content such as photos and videos, showing who made it, with which tools, and how it was edited. It helps people check whether something was made with AI.
C2PA is a set of rules built together by companies such as Adobe, Google, Microsoft and OpenAI. It attaches a history label called Content Credentials to a file. The label records who made it, when, with which tools, how it was edited and whether AI was used, and it carries a digital signature. C2PA compares this to a nutrition label on food. If someone secretly changes the file or the label, the signature no longer matches, so the change shows.
Watch out The C2PA explainer says this label only tells you where content came from; it cannot tell you whether the content is true. The label can also be removed, so a missing label does not prove a person made something. That is why some tools pair it with an invisible watermark.
Source: Home · C2PA and Content Credentials Explainer · How it works - Content Authenticity Initiative (checked 2026-10-26)