It is unlawful for any person to sell, offer for sale, or give away a dead animal or convey the same along any public road or land not his or her own: PROVIDED, That dead animals may be sold or given away to and legally transported on highways by a person having an unrevoked, annual license to operate a rendering plant or by a person having an unrevoked, annual license to operate as an independent collector.
RCW 16.68.030