[Chickensoup]

Probably by part of the country and time frame of birth.

[Cementjungle]

Probably by part of the country and time frame of birth. Sperm can remain frozen for many years before someone buys it. So the birth date of the kid is no clue as to when it was donated. Plus, the sample could have come from anywhere in the US or Canada.

If someone contacted me and said "one of your relatives, sometime before 5 years ago, donated sperm to a sperm bank. Do you know who that was?" I wouldn't have a clue... I have all sorts of cousins, nephews, uncles, etc.