Registration...solution???
I've been stopped by IL EPA to ask for registration - that particular state requires registration for personal watercraft on public waters (but not if you owned land that contained a lake/pond and paddled only on that waterway). IL supplies stickers w/ registration, and as the previous post mentioned, keeps serial #s as part of their paperwork. If there ever was a dilemma, it could easily be sorted out. I've heard, anecdotally, that one woman at DNR actually handles ALL of the boat registration for the entire state! How cool is that....
NOW - would you EVER put the IL registration sticker on a wooden canoe????
Just as a note, my current state (CT) doesn't require registration, so it's a little less clear what you would do here. BUT - here's the kicker - I just re-registered the boat back in IL (haven't lived there in years) for an upcoming canoe trip in the state - it wasn't at all clear what one should do if you live out of state but use a personal watercraft in IL. Furthermore, I'll be canoeing right by an IL EPA station so I didn't want any ambiguity! I didn't think that IL would process the paperwork for someone who lives out of state, but I just submitted it, paid the small fee, and now I have registration stickers on the boat through 2011.
SOLUTION
So the moral of the story (and I don't know if this is true for everyone, or even legal, but I can't find any reason why it wouldn't be) - if you REALLY, REALLY wanted some type of legal documentation that you "owned" or at least previously registered a boat, you could register your boat in IL w/ a cover letter saying it's for an upcoming trip, they ask for serial numbers dates of purchase, but don't require paperwork to that effect. Then a few months later, you get back a formal registration card, w/ your name and the boat's serial number on it. That should just about take care of ANY controversy if someone claims that your boat is theirs in the future... And even if you never update the registration, just hold onto the paperwork. And all and all, I think it cost less than $10-15...