To commercially grow shellfish in waters of the State of Oregon, you must apply for a lease of a shellfish plat (ORS 622.210-220).
Shellfish plat information
Rules relating to Shellfish Sanitation Oregon administrative rules: Shellfish sanitation
Rules relating to Shellfish Plat Leasing Oregon administrative rules: Oyster, clam, and mussel leases
Oregon revised statutes 622: Shellfish
Shellfish plat application for state-owned estuary lands. Shellfish plat application
Annual shellfish plat production report as of February 26, 2018. Shellfish plat production report