WAC 308-104-0150
WAC 308-104-0150. Changing sex designation on a driver's license, instruction permit, or identification card
(1) Persons may change the sex designation on a driver's license, instruction permit, or identification card by means of completing a sex designation change application signed under penalty of perjury pursuant to chapter 9A.72 RCW.
(2) For the purposes of this section, "X" means a sex that is not exclusively male or female.