Yes, it's really common. Most universities actually support this and there is a specific contractual framework for staff which basically says "If you create a company during or after your work at university which touches the field you were researching in, we get 1% (or 10% or 20%) of your annual revenue as license fees".

The alternatives are lengthy court battles between universities and their best (e.g. most commercial) researchers. This creates bad PR for the university and uncertainty for the researcher & their startups because potential investors don't like open court cases.

So people came around to make this kind of license fee contract and researchers check it before deciding to join a certain university.

Not a fan of gene / bacteria patents though.