requiresSubscription

Thing > Property > requiresSubscription

Indicates if use of the media require a subscription (either paid or free). Allowed values are true or false (note that an earlier version had 'yes', 'no').
Values expected to be one of these types
Boolean
MediaSubscription
Used on these types
ActionAccessSpecification
MediaObject

Source

https://github.com/schemaorg/schemaorg/issues/1741