grant_banner_house_claim_effect

grant_banner_house_claim_effect = {
	save_scope_as = familial_banner
	hidden_effect = {
		if = { # Dynasty banner not owned or claimed by all child house's already
			limit = {
				exists = var:banner_dynasty
				var:banner_dynasty = {
					any_dynasty_member = {
						this = house.house_head
						house = { artifact_house_not_owns_or_claims_trigger = yes } # House not owns or claims already
					}
				}
			}
			var:banner_dynasty = {
				every_dynasty_member = {
					limit = {
						this = house.house_head
						house = { artifact_house_not_owns_or_claims_trigger = yes } # House not owns or claims already
					}
					house = { add_house_artifact_claim = scope:familial_banner }
				}
			}
		}
		else_if = { # House banner not owned or claimed by creating house already
			limit = {
				exists = var:banner_house
				var:banner_house = { artifact_house_not_owns_or_claims_trigger = yes } # House not owns or claims already
			}
			var:banner_house = { add_house_artifact_claim = scope:familial_banner }
		}
	}
}

As written in game/common/scripted_effects/00_ep1_artifact_effects.txt.