json.scala

object A {
	sealed trait LotLinkType
	object LotLinkType {
		case object Tenant extends LotLinkType
		case object Owner extends LotLinkType
		case object Landlord extends LotLinkType
	}
	
		implicit val TenantJsonFmt = jsonSerializeCaseObject(Tenant)
		implicit val OwnerJsonFmt = jsonSerializeCaseObject(Owner)
		implicit val LandlordJsonFmt = jsonSerializeCaseObject(Landlord)
	implicit val LotLinkTypeJsonFmt = new Format[LotLinkType] {
		override def reads(json: JsValue): JsResult[LotLinkType] =
			__.read[Tenant.type].map(x => x: LotLinkType)
				.orElse(__.read[Owner.type].map(x => x: LotLinkType))
				.orElse(__.read[Landlord.type].map(x => x: LotLinkType)).reads(json)

		override def writes(o: LotLinkType): JsValue = o match {
			case Tenant => Json.toJson(Tenant)
			case Owner => Json.toJson(Owner)
			case Landlord => Json.toJson(Landlord)
		}
	}
}	

object B {
	
	import PatrimonyContactEventModelJsonFmt.LotLinkTypeJsonFmt

    Json.toJson(Tenant).validate[LotLinkType]
	Json.toJson(Owner).validate[LotLinkType]
	Json.toJson(Landlord).validate[LotLinkType]
}	

if i cast Tenant with LotLinkType
Json.toJson(Tenant: LotLinkType).validate[LotLinkType] that compil