Sorry it took so long to get back to you with an answer! Also no snark detected. Here is a nice overview by the SEC but it's really light on the details.

https://www.sec.gov/investor/pubs/regsho.htm#_ftn4

You can also look through FINRA's regulations here:

https://www.finra.org/rules-guidance/rulebooks

The wikipedia article on Regulation SHO is also fairly relevant:

https://en.wikipedia.org/wiki/Naked_short_selling#Regulation...

It's pretty long and tedious and not really targeted to your question though. I'll try to remember to post a better resource here when I find one.