99designs uses a built-in declaration mechanism in its contest submission workflow that requires designers to disclose whether they used generative AI tools, and the platform enforces a categorical ban on AI-generated content in logo, illustration, and button/icon design contests. This is a platform-level policy control rather than an automated AI detection system.

When submitting a contest entry, designers are prompted to declare whether generative AI was used and, if so, which tool. In categories where AI is banned (logo, illustration, button and icon design), no AI-assisted submissions are permitted under any circumstances. 99designs' own support documentation states that the platform has 'systems in place to catch designs that do not follow our guidelines,' though the exact technical nature of these systems — whether AI-assisted or manual — is not confirmed in publicly available sources. The disclosure requirement is a workflow enforcement mechanism embedded in the submission process.