Cat hairloss

Question
My cat Sneakers is approximately 12 years old, and I just noticed today that he has a bald spot on his side, as if someone just shaved the hair right off. It does look like the skin where the hair came out was very slightly irritated. He let me touch the spot, with no problem, so the area doesn't seem to bother him. My cat is an indoor cat amongst 2 other indoor cats that are all healthy. Any idea what this could be? He does get in to little fights with one of the other cats, nothing serious, but he has gotten a nick or two from the other cat.

Answer
This could be allopecia, which is a hair loss in partial areas. A lot of the time it is self-inflicted from excessive licking. The redness you see would correlate with that.
Allergies to fleas, rugs and other things are possible causes.
Best to have him looked over by the vet and he/she can best determine what the cause might be.