Daily limit vs. multiday limit (lingcod)

A buddy was camping on the coast here in Mendo and went out fishing Thu. (and caught one lingcod) and then with me on Fri. (and caught another) and stopped fishing because he was worried that he could get in trouble if he caught more than one lingcod because back at his campsite, in his cooler, he had the Thu. lingcod and if he caught two on Friday he'd have three in possession.

How do daily limits work over multiple days? If he fished for three days could he conceivably have six lingcod in his cooler?

And are the regulations around this different for different species?

Update: Found this addressed in this old thread.

https://www.norcalkayakanglers.com/index.php?topic=53524.0

Bag Limit (meaning catch on one calendar day) vs. In Possession (meaning what it implies). Apparently they're usually the same thing. In my scenario my buddy would only be able to have two lingcod in his cooler, but there's some gray area if he "gave" some fish to his wife and they were in the same cooler. Hmmmmm...