Operationalization is comparatively concrete here but still narrow. EU AI Act Article 50(2), enacted in Regulation (EU) 2024/1689 and generally applicable from 2 August 2026, requires providers of AI systems, including general-purpose AI systems, that generate synthetic audio, image, video, or text to mark outputs in machine-readable form and make them detectable as artificially generated or manipulated, as far as technically feasible. The obligation is qualified by content-specific limits, implementation costs, the generally acknowledged state of the art, and exceptions for standard editing that does not substantially alter input data or semantics and for certain law-enforcement-authorized uses. C2PA provides cryptographically verifiable Content Credentials and related provenance specifications. Google SynthID embeds watermarks in AI-generated images, audio, text, and video across Google generative products; the DeepMind page describes Gemini and SynthID Detector checks for uploaded image, video, and audio, while SynthID Text detection is documented separately as probabilistic detector tooling for text generated by models using SynthID Text.

However, open-web verification remains brittle. C2PA-style provenance metadata can help track source and history, but the source paper notes that metadata can be stripped from content. Watermark detection generally applies to participating generators and known watermark schemes, not all open-web content. SynthID Text detection is probabilistic and Google documents that confidence can be greatly reduced by thorough rewriting or translation. General ex post detection of unwatermarked content from unknown models remains unreliable in the sources reviewed here: the source paper says detectors have not always held up to independent evaluation and will become harder to maintain as generators improve, and the SynthID-Text Nature paper describes post hoc text detectors as limited by inconsistent performance, poor out-of-domain performance, false-positive risks for some groups, and likely need for continual maintenance as LLMs improve.