well to be honest with you I think he was pushed off the corner, in which case he doesn't need to concede his lead. The stewards didn't call him back either, which leads me to believe that he was in fact being defensive by avoiding contact. After that, he kept the lead and in the following chicane he gave de la Rosa a window to pass which de la Rosa didn't take. After that the race was back on.

I don't know though. I'm going to wait for some post race reports to make my decision on what really happened.