Source: Schema.org v30.1 vocabulary. Official sender property definition.
What does sender mean?
A sub property of participant. The participant who is at the sending end of the action.
Parent properties
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