I don't think that SAT scores are a good indicator of future career success because you can't base someone's life just on one test. Especially since the day that person took the test they could've been sick or just had a bad day overall. The SAT can't see how hard a person works, their work ethic, and some of their problem solving skills. Therefore if a company doesn't hire someone based on their SAT scores they might be losing out on a very valuable worker.
There shouldn't be an expiration date on the scores because the scores shouldn't even be used on an employee's application. If there was an expiration date maybe it could be based on when the SAT company changes the formation on the SAT because therefore it would be irrelevant for the people that have already taken the test.
I think some employers might penalize the person by simply not hiring them but if they did hire them that person would have to start out at a really low level entry job. Personally I don't think the SAT scores should be used so there shouldn't be any penalties. The job should go to someone who can get it done efficiently and the right way.