(1) The claimant, the claimant's attorney, or the claimant's agent shall sign the claim and include in the claim the following information:
(a) The name and address of the claimant;
(b) The name, address, if different from that of the claimant, and nature of authority of an agent signing the claim on behalf of the claimant;
(c) A statement of the facts or circumstances constituting the basis of the claim;
(d) The amount of the claim; and
(e) If the claim is secured, unliquidated, contingent, or not yet due, the nature of the security, the nature of the uncertainty, or the date when it will become due.
Failure to describe correctly the information in (c), (d), or (e) of this subsection, if the failure is not substantially misleading, does not invalidate the claim.
(2) A claim does not need to be supported by affidavit.
(3) A claim must be presented within the time limits set forth in RCW 11.42.050
by: (a) Serving on or mailing to, by regular first-class mail, the notice agent or the notice agent's attorney a copy of the signed claim; and (b) filing the original of the signed claim with the court in which the notice agent's declaration and oath were filed. A claim is deemed presented upon the later of the date of postmark or service on the notice agent, or the notice agent's attorney, and filing with the court.
(4) Notwithstanding any other provision of this chapter, if a claimant makes a written demand for payment within the time limits set forth in RCW 11.42.050
, the notice agent may waive formal defects and elect to treat the demand as a claim properly filed under this chapter if: (a) The claim was due; (b) the amount paid was the amount of indebtedness over and above all payments and offsets; (c) the estate is solvent; and (d) the payment is made in good faith. Nothing in this chapter limits application of the doctrines of waiver, estoppel, or detrimental claims or any other equitable principle.