I'm hoping that someone here can help me with an unusual green card question.
I lived in the US with my partents when I was in elementary school - we moved there on a visa for a year but then got green cards through the green card lottery at the end of the first year. We stayed 4 1/2 years but then went back home in 1997 since my grandparents were sick. My dad had to stay an extra six months to finish his contract and sell the house and so he successfully applied for citizenship. The plan at the time was to return to the US in a year or so.
In the end we didn't return so I have now just discovered that I have a green card which shows an expiry date in 2002.
I've heard stories about people entering the US on a sort visit many years after a green card expires having a problem at security - being taken off and asked questions for several hours and then being asked to sign a form formally revoking their green card. I've recently started a job where I travel to the US for meetings occassionally and I'd like to avoid this, or any other problems in the future (I might want to work in the US some day).
Is there anything I should do to regularise my status? Do I really need to formally revoke a card that expired 15+ years ago? If my green card holding status has been valid all this time should I have been submitting tax returns since I was 18?