Continuity mistake: Season 5 - Episode 3. After Turk has operated on the patient without anesthetics and Dr. Cox says they can publish it in Almost Magazines, the clock on the wall to the right of the screen shows 11:05. When it cuts the clock shows 5:40.
Continuity mistake: Season 5 - Episode 3. When JD lies on the ground and Elliot is trying to help him up, the paper cups lying around JD's head change position between the shots.
Revealing mistake: In the scene where J.D. first starts the bike portion of the triathlon, you can see his feet pedaling. You can see that there is no chain on the gears, allowing him to exaggerate the speed he is pedaling.
Answer: No, it was a fake, they used a stamp.
It is real.