(1) For purposes of calculating the date that written submissions to the arbitrator under RCW 48.49.040 are due, final selection of the arbitrator occurs on the date that the commissioner sends by electronic transmittal the notice of selection to the arbitrator. The parties must be copied on such notice.

(2) Good cause for purposes of delay in written submissions to the arbitrator under RCW 48.49.040 includes a stipulation that the parties intend to complete settlement negotiations prior to making such submissions to the arbitrator.

(3) If the parties agree on an out-of-network rate for the services at issue after submitting an arbitration initiation request but before the arbitrator has made a decision, they must provide notice to the commissioner as provided in RCW 48.49.040(7).

(4) If an initiating party withdraws an arbitration initiation request at any point before the arbitrator has made a decision, the party must submit to the commissioner notice of the date of the withdrawal of the request, as soon as possible, but no later than three business days after the date of the withdrawal.

(5) Any enrollee or patient information submitted to the arbitrator in support of the final offer shall be de-identified to ensure that protected health information is not disclosed.

(6) The decision of the arbitrator is final and binding on the parties and is not subject to judicial review. The arbitrator must submit to the commissioner:

(a) Their decision, including an explanation of the elements of the parties' submissions the arbitrator relied upon to make their decision and why those elements were relevant to their decision; and

(b) The information required in RCW 48.49.050 using the form found in Appendix B to this rule, or for arbitration proceedings under RCW 48.49.135, using the form found in Appendix C to this rule.

(7)(a) For the calendar year beginning January 1, 2023, arbitrators must charge a fixed fee for single claim proceedings within the range of $200-$650. If an arbitrator chooses to charge a different fixed fee for bundled claim proceedings, that fee must be within the range of $268-$800. Beginning January 1, 2024, and January 1st of each year thereafter, the arbitrator may adjust the fee range by the annual consumer price index-urban as determined annually by the United States Bureau of Labor Statistics.

(b) Expenses incurred during arbitration, including the arbitrator's expenses and fees, but not including attorneys' fees, must be divided equally among the parties to the arbitration. Arbitrator fees must be paid to the arbitrator by the parties within 30 calendar days of receipt of the arbitrator's decision by the parties.

(c) If the parties reach an agreement before the arbitrator makes their decision, the arbitrator fees must be paid by the parties within 30 calendar days of the date the settlement is reported to the commissioner as required under RCW 48.49.040.

(8) RCW 48.49.040(13) governs arbitration proceedings initiated under RCW 48.49.135. The determination of the rate to be paid to the out-of-network or nonparticipating provider must be accomplished through a single arbitration proceeding.