Not sure but he may have missed it. At the time the controller was working 2 sectors on 2 frequencies at the same time. He was working approach on 120.1 as well as departure on 121.3 at the same time. When it happened I was actually listening to approach and missed the initial call from 1848. Also up until about 1 minute or so, a female controller was working the radio. They may have caught them right in the middle of a controller change. The other possibility is with departures off of the 30's at SJC need to make a turn back south with in couple miles of the airport to avoid running into SFO "Modesto" arrivals which are dead ahead. Those arrivals are worked by another controller and playing back the noise monitor radar, it looks like there might have been a conflict with UAL 37 if they had gone straight out for SFO. But since none of us were there when it happened hard to know exactly what happened.