Wash. Rev. Code § 11.11.110
Notwithstanding RCW 11.11.100, a financial institution or other third party having actual knowledge of the existence of a dispute between beneficiaries, a testamentary beneficiary, or other persons concerning rights to a nonprobate asset under this chapter may condition transfer of the nonprobate asset on execution, in form and with security acceptable to the financial institution or other third party, of a bond in an amount that is double the fair market value of the nonprobate asset on the date of the owner's death or the amount of any adverse claim, whichever is the lesser, indemnifying the financial institution or other third party from any and all liability, loss, damage, costs, and expenses, for and on account of transfer of the nonprobate asset.
RCW 11.11.110