May be you account can be permanently blocked by google after some days. if you using same ip address in 2 accounts?
i believe they will only do it a) if they think it is the same person b) one of you had an account closed before by google you can run different companies accounts using same IP no issue as many people manage numerous accounts (but i am sure the companies arent all listed at the same address)
Then in that case the question was about having 2 adsense account -- that is against the terms and conditions and will get both accounts banned when detected.