Apparently there was a tradition at this dojo where if it was a student's birthday, the rest of the dojo would be allowed to throw them three times.
Ronda Rousey was in attendance on this particular day, much to the chagrin of the male brown belt who was due to be tossed.
The video was taken sometime in 2008, right before she left to Beijing to compete in the Olympics.
Some fight fans on MMA forums insist that Rousey was being a bully by throwing around a teenage boy on his birthday, but it might be quite the opposite.
In this case, the birthday judo throws served the same purpose as "birthday punches."
In French-speaking Canada and the U.S. "birthday punches" are given for luck, not in a mean-spirited manner.
Quite often, the person whose birthday it is gets punched a number of times equal to his/her age, often with one additional punch "for luck".
Rousey's judo tosses to celebrate this student's birthday was performed in the same manner, with no intent to harm, hurt or bully him.
In fact, Rousey and the student share a warm embrace at the end of the clip.
It was this particular student's birthday and Rousey tossed him as part of a tradition. Many sports and organizations have hazing rituals like this, so this instance was no different.