I've looked at a few sites owned by those who know the ways of the web and web advertising in an out.

Some run 4 adsense ads per page.

I have three on each page but selectively started adding a fourth.

When I check the AdSense help files, it mentioned only three ads are allowed. So I changed all the fourth ads to Ad Units (though they don't seem to do as well as the other ads).

I haven't read the TOS for some time; recently did but can't, unless I missed it, find anything about the number of ads.

Does anyone know if there is a limit on the number of ads that can be run on a page. Thank you.