Although others will certainly disagree, before I had my CDS, I walked around for nearly three years with my original passport and my visa. Yes, make sure you have copies of your visa as well. I didn't put my passport away until I got my CDS. Then again, there is that three day rule for proof but my logic has always been, don't look for trouble. Warm regards!I don't have a Carte De Sejour, but I have multiple copies of the first page of my passport, on my laptop and on paper. Maybe I should make a copy of my visa as well?