The artifact is protected by a soft or “porous” paywall.
Online journalistic content that is partially restricted from free public access, whether through a metered content system, mandatory registration, or a referer based model that allows content to be viewed when linked from specific other sites, is said to be protected by a [soft paywall][sp]. [sp]: https://en.wikipedia.org/wiki/Paywall#%22Soft%22_paywalls
The Soft Paywall flag can be applied to a specific media artifact or to a publisher or other entity. When applied to an artifact, it indicates that the artifact is protected by a soft paywall. When applied to an entity, it indicates that the entity utilizes a soft paywall in the publication of its content.