Is there a way to know who the actual manufacturer is of a store-brand over-the-counter drug?

Example: I was at a grocery and purchased a container of Kroger-brand Ibuprofen. I’m pretty sure that Kroger doesn’t do their own manufacturing, so some other company made and bottled the pills.

Is there a way to know who?

(and this goes for WalMart, target, Walgreens, CVS, and zillion other stores that are putting their own name on a pill or a liquid)