Source: Schema.org v30.1 vocabulary. Official programMembershipUsed property definition.
What does programMembershipUsed mean?
Any membership in a frequent flyer, hotel loyalty program, etc. being applied to the reservation.
Used on types (domainIncludes)
Expected value types (rangeIncludes)
Schema.org domainIncludes and rangeIncludes are descriptive guidance, not strict validation prohibitions. Check the official reference for updates.
Related reference
Browse all Schema.org types and properties · Google feature support status