I had applid for US Green Card 5 yrs back and my I485 is still pending. In the mean time, also applied for CA Green Card which is also at the final phase. I  am hoping both will be approved almost at the same time.

Now my question is, Is it allowed to keep both Green cards? I  know US allows dual citizenship but here the case is different. Somewhere I read that, you have to give up one if you receive another- not sure how true is that. I know there are few restrictions of stay period, you need to stay at least 2 yrs in CA to keep PR or things like that.