A survey is authenticated not by the fact that a surveyor’s stamp is upon it. This alone is inadequate.
In addition to the stamp, the surveyor must place his or her signature and the handwritten date of the survey’s completion across the stamp.
Notably, in the past the expiration of the surveyor’s current license (which must be renewed every two years) had to also be included.
Vic Banks who is retired but remains active as teacher in the survey field, related that this expiration date could be handwritten, but was usually placed within the stamp itself.
Yet, I noted that some of the more recent surveys did not have the expiration date on the stamp. It appears that at some point the legislature dropped the requirement that the expiration date be on the survey stamp itself. RCW 18.43.070 states in pertinant part:
It shall be unlawful for anyone to stamp or seal any document with said seal or facsimile thereof after the certificate of registrant named thereon has expired or been revoked, unless said certificate shall have been renewed or reissued.
So, it appears that if there is a reaon to question the authenticity of a survey in full (as opposed to components within), one means would be to seek to disaffirm that the surveyor was in fact licensed during the date that the surveyor affixed his or her stamp, signature, and date to it.
Moreover, where there is simply a survey with a stamp and nothing else, the survey certainly is not self-authenticating.
In such a situation, the question becomes whether the Court will or will not allow it in as parole evidence. I would be interested to hear more about how successful that attempt has been in the past. If you have any experience as a surveyor or as an attorney in this regard, please feel free to share.