<<Disclaimer: Verify this information before applying it to your situation.>> I have called China Bowl, a manufacturer of oyster sauce, and they informed me that their oyster sauce is g.f. I use fermented black beans a lot and never questioned if they were g.f. (anything that smells that bad must be o.k.)and there hasn't been a problem. I don't know about the fish sauce, but I will check the label on the bottle I have. Barbara Gaumond Hopkinton, MA [log in to unmask]