This has been posted and even trolled about a lot *sigh* I'd recommend doing searches, refining them carefully, instead of just opening up a new thread.

When you have extraction points, you'll see that quota. That refers to the Refinery structure that you can build after sufficent research. If you build enough refineries to fulfill that quota (if it's a 3, then you build 3 refineries), then you'll have maximum resource income. Now, here's the kicker. Those refineries support all extraction points in the system they are built and adjacent systems (immediately surrounding systems connected through a single phase lane). That means you can strategically position a set of refineries at a central planet and it'll support all surrounding planets. Remember this fact, as refineries use up logistical slots, which you only have so much of. You need those for trade, culture, or factories.

I should note that extraction points surrounding uninhabitable locations (gas giants, asteroid belts, etc.) require 4 refineries, which suggests that an inhabited planet offers it's on refinery support within the grav well, which lowers the overall quota to 3, instead of 4. Pure speculation and imagination, but just something. Just remember, you need 4 to fully support those other extraction points.

Hmm, well, if you came up with no hits, then cool. Strange. Maybe the topics I read weren't titled concerning refinery quota's, but were going into them in depth. Perhaps that's why you didn't get any hits even though there is a lot of that info around.

Well, whether that was the case or not, now we've got a dedicated thread that people can search for. And thanks for your simple and to the point topic title. It really gets annoying when people make new threads with a title "Please Help" or whatever. You've just turned from a potential nuisance to awesome because of this thread I'll have to be diplomatically apologetic here, since I've been dealing with a lot of trolls in the short time I've been posting here, and it's really gotten on my nerves, so please, take no offense in my stating that you were a potential nuisance. Just my temper on edge.

Edit: Sorry for the double post, internet lagged out.

The SoaSE Wikia article explains it better than I could.

It's a wonderful resource - just a pity it's not been updated for Entrenchment (yet?).