ISO options have to expire within 10 years of when they are granted. Sometimes companies make them expire earlier than that, so OP might be thinking of options they were granted. E.g. I once had options that expired 30 days after ending employment even thought the ISO requirement is up to 90 days.
You have to exercise the options or let them expire. You normally have 10 years not 7, but if a company comes up on 10 years after they issued their first options, they might try a tender offer to buy some employee shares. If your 10 year old "start up" shares can't be sold anywhere, then they probably aren't worth exercising. A company that can't provide liquidity to employees for 10 years will probably never do it.
