The primary and official contact page URL for an entity, such as but not limited to a link to a contact form, a website with aggregate contact details. A URL whose main purpose is not to provide contact details but happens to have some contact information on it should not be used. A social URL should not function as the primary and official contact page URL for an entity.
Citation Requirement
Optional – A citation is optional for triples with this predicate.
'Marc Andreessen' → 'Contact Page URL' → 'https://twitter.com/pmarca' is incorrect, as a Twitter URL does not function as the official Contact Page URL for an entity.