I also think Sno County screwed up
If you decide to fight this, take it to the State or Federal level. I'd hate to bring this up to another County Auditor because they might decide to go with Snohomish County! A Sno County friend went in to the office in person to renew a 1970s boat and had no trouble. His HIN is not quite in the format for 2012, but it is closer than mine. I had no trouble three weeks ago for my 1980 and got mine from the Pierce County Auditor via the WA DOL online renewal and the US mail.
Here are the applicable Federal regulations from your link. These are Manufacturers Requirements. I think the folks at the Snohomish County Auditors Office have interpreted the requirements incorrectly and if they checked with "somebody" they would likely be told that the rule in 181.23 only applies to HIN location and the need for a hidden duplicate number. It seems they are out of step with the rest of Washington State. This regulation does not seem to demand that anyone who is not manufacturing boats change his hull id number on already-produced hulls. If there is no hull number at all, then you make one up, is how a reasonable person would interpret this, IMHO. In any case, for documented boats, a new HIN must be coordinated with the USCG. The document on the HIN format is from 1984, which makes many of our boats prior to that format rule. If the number is unique by virtue of the ERY designation, then I see no reason to change it. My boat is documented and has been renewed by the USCG for 13 years.
§ 181.23
Hull identification numbers required.
(a) A manufacturer must identify each boat produced or imported with primary and secondary hull identification numbers permanently affixed in accordance with § 181.29 of this subpart.
(b) A person who manufactures or imports a boat for his or her own use and not for sale must obtain the required hull identification number in accordance with the requirements of the issuing authority listed in 33 CFR part 173, Appendix A for the boat's State of principal operation and permanently affix the HIN to the boat in accordance with § 181.29 of this subpart.
(c) No person may assign the same HIN to more than one boat.
[USCG-2003-14963, 77 FR 18703, Mar. 28, 2012]
§ 181.25
Hull identification number format.
Each of the hull identification numbers required by § 181.23 must consist of twelve characters, uninterrupted by slashes, hyphens, or spaces, as follows:
(a) The first three characters must be a manufacturer identification code assigned under § 181.31(a) or the importer designation assigned under § 181.31(b).
(b) Characters four through eight must be a serial number assigned by the manufacturer in letters of the English alphabet, or Arabic numerals, or both, except the letters I, O, and Q.
(c) Characters nine and ten must indicate the month and year of certification when a date of certification is required. In all other cases characters nine and ten must indicate the date of manufacture. The date indicated can be no earlier than the date construction or assembly began and no later than the date the boat leaves the place of manufacture or assembly or is imported into the United States for the purposes of sale. Character nine must be indicated using letters of the English alphabet. The first month of the year, January, must be designated by the letter “A”, the second month, February, by the letter “B”, and so on until the last month of the year, December. Character ten must be the last digit of the year of manufacture or certification and must be an Arabic numeral.
(d) Characters eleven and twelve must indicate the model year using Arabic numerals for the last two numbers of the model year such as “82” for 1982 and “83” for 1983.
§ 181.29
Hull identification number display.
Two identical hull identification numbers are required to be displayed on each boat hull.
(a) The primary hull identification number must be affixed—
(1) On boats with transoms, to the starboard outboard side of the transom within two inches of the top of the transom, gunwale, or hull/deck joint, whichever is lowest.
(2) On boats without transoms or on boats on which it would be impractical to use the transom, to the starboard outboard side of the hull, aft, within one foot of the stern and within two inches of the top of the hull side, gunwale or hull/deck joint, whichever is lowest.
(3) On catamarans and pontoon boats which have readily replaceable hulls, to the aft crossbeam within one foot of the starboard hull attachment.
(4) If the hull identification number would not be visible, because of rails, fittings, or other accessories, the number must be affixed as near as possible to the location specified in paragraph (a) of this section.
(b) The duplicate hull identification number must be affixed in an unexposed location on the interior of the boat or beneath a fitting or item of hardware.
(c) Each hull identification number must be carved, burned, stamped, embossed, molded, bonded, or otherwise permanently affixed to the boat so that alteration, removal, or replacement would be obvious. If the number is on a separate plate, the plate must be fastened in such a manner that its removal would normally cause some scarring of or damage to the surrounding hull area. A hull identification number must not be attached to parts of the boat that are removable.
(d) The characters of each hull identification number must be no less than one-fourth of an inch high.
[CGD 79-013, 48 FR 40718, Sept. 19, 1983; 48 FR 53558, Nov. 28, 1983]