Google Search now supports specifying where (which regions) a video is not allowed to be viewed in its video structured data and video SEO documentation. A new ineligibleRegion property was added to the Google video structured data documentation.
The ineligibleRegion property lets you specify the region where the video isn't allowed. If you do not specify this property then Google will assume the video is allowed everywhere.
You can specify the countries in two or three letter ISO 3166-1 format. For multiple values, use multiple country codes (for example, a JSON-LD array or multiple meta tags in Microdata).
Google also supports the regionsAllowed property, if you prefer to only specify where the video is allowed versus specifying where the video is not allowed.
Google added these details to the video docs saying:
If you use VideoObject structured data to describe a video, set the regionsAllowed property to specify which regions can get the video result. If you omit this property, all regions can see the video in search results.Alternatively, you can use the ineligibleRegion property to specify which regions can't get the video result.
Here is how to specify the video is not allowed in the US:
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