Just keep in mind that you haven't actually "gained" anything until you sell. I was up well over 50% in a couple of months when I sold on Tuesday. Would my profit on GRPN have been more if I'd waited until today to sell? Yes, but that money is working somewhere else for me, now. If GRPN doesn't keep going up, and trades sideways or, worse, goes back down, you'll have gained nothing if you sell. You can hold even then, but it might never go back up. Sometimes it's a good idea to take money off the table. Greed, in my experience, usually makes you poorer. Good luck, though.