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Explicit treatment of, and allowance(s) for, a broad range of 3rd party content including:

• Content not owned by the website owner (e.g., movies, ads, maps, etc.) where copyright restrictions or license agreements may prevent the website owner from changing the content to make it accessible.
• Content shared by individual website visitors (e.g. comments, blog posts, social media posts, recorded media). While a website may offer authors (visitors) the ability to submit accessible content, we are concerned with the impact of holding sites accountable by requiring visitors to submit content through an accessibility assessment and remediation pass (e.g., having to put ALT text on every image they contribute; having to meet language simplicity rules for readers with print/cognitive impairments). Doing so places a burden of specialized knowledge on the part of content contributors, and so could result in contributors “gaming the system”, such as adding garbage ALT text to pass the content posting requirement. It could also lead to a large drop in content sharing.