Are there quotas for target schools?

I know that some firms do school-specific superdays where they'll interview everyone at your school during the same few days if you do to a strong target for them. Can anyone speak to if there are actually "quotas" of how many students they take from each target school then or from the superday? Do schools become "targets" for a firm because the firm agrees to take a certain number of kids from the school each year? Not that it changes much in your attitude interviewing, but curious.