John & Angela wrote:
I doubt that immigration and customs personnel would even know what an IRS form like the 8840 is. My guess is they will never ask for it.
All it takes is to meet up with one Agent who thinks it's needed and if you can't produce it you're denied entry.
My experience with Canadian Customs: I used to be sent to Canada periodically for a minor work related activity. The last time I was sent I ran into a Customs Officer who asked for a copy of my company's contract that authorized my visit, and I didn't have it so I was denied entry. The company lawyers and import/export officers had never heard of such a requirement and couldn't find any reference to it, but they provided me with a copy of the contract and pointed out the most likely paragraph that would satisfy Canadian Customs. The next day I returned and as luck would have it I met the very same Canadian Custom Agent who remembered me from the previous day. He asked me if I'd been turned back by him previously and why and if I had the proper paperwork this time. I answered his questions and provided him with the contract, but it was clear from the look on his face he had no clue what to do next. I politely pointed out the paragraph that he was probably looking for, he read it handed it back to me and wished me a good trip.
A few years later I was traveling to Alaska and went in and out of Canada a couple of times. Upon each entry into Canada I was asked about this prior incident and was finally told that I'd been flagged in the Canadian Customs database, so they had to ask. I was never denied entry, just had to have a prolonged discussion with them. However, on one re-entry into the US I was asked by US Customs why I'd been flagged in Canada. Obviously the data had been shared.
The amusing part of this to me was the contract was one between the Canadian and US Governments.