Unfortunately, there is a corollary: "If you ignore coworkers' pranks, the coworkers will eventually find a prank that you cannot ignore."
For example, if they put some tacks on your chair and you shrug it off, one morning you will find a sewing needle embedded into your chair. Walk away from your desk for a minute and, upon returning, taste $something_bad in your coffee. Bullies can be very inventive if they are unopposed. Sometimes it ends up in murder, just because the bullies, being sadists by definition, wanted to push the situation just a little farther.
In this case Intel will have to part with a significant sum of money for allowing the hostile work environment to exist for so long. I am sure the guy complained to his boss, but that was ignored. If the guy also complained to HR and was ignored there as well, he won't need to worry about coworkers for the rest of his life.