Wash. Rev. Code § 48.44.470
For the purposes of this chapter, a nonresident pharmacy is defined as any pharmacy located outside this state that ships, mails, or delivers, in any manner, except when delivered in person to an enrolled participant or his/her representative, controlled substances, legend drugs, or devices into this state.
After October 1, 1991, a health care service contractor providing coverage of prescription drugs from nonresident pharmacies may only provide coverage from licensed nonresident pharmacies. The health care service contractors shall obtain proof of current licensure in conformity with this section and RCW 18.64.350 through 18.64.400 from the nonresident pharmacy and keep that proof of licensure on file.
The department may request from the health care service contractor the proof of current licensure for all nonresident pharmacies through which the insurer is providing coverage for prescription drugs for residents of the state of Washington. This information, which may constitute a full or partial customer list, shall be confidential and exempt from public disclosure, and from the requirements of chapter 42.56 RCW. The board or the department shall not be restricted in the disclosure of the name of a nonresident pharmacy that is or has been licensed under RCW 18.64.360 or 18.64.370 or of the identity of a nonresident pharmacy disciplined under RCW 18.64.350 through 18.64.400.
RCW 48.44.470
Effective date-1991 c 87: See note following RCW 18.64.350.