The AdSense ads of only ONE publisher can be displayed on a single PAGE. The ads of different publishers can be on different pages.
That would depend on the TOS of whatever advertising program you happen to be talking about. I know you don't mean AdSense, of course, since this is the wrong forum for that. -Michael
As far as I know it's legal, but they don't recommend it because if a page violates the TOS for other reasons, both publishes get the axe.
Your site can have many different publishers (there's no limit), and this forum is a good example with his ad revenue sharing system. But as CountryBoy said: on a single PAGE you must put the AdSense ads of only ONE publisher. Although you can rotate and change the publisher for the same page later .
Best not to think too deeply about it. Google write the checks and they say it isn't allowed. End of story. Maybe you should get acquainted with the AdSense Program Policies and Terms and Conditions - judging by your blog I envisage that you and Google are going to disagree on things in the future.
You guys have no idea, it is perfectly legal for multiple adsense IDs to be placed on one page. As long the page doesn't go over the maximum of 3 ads and 1 link unit, you are fine. This was the response I received couple months ago, "I understand you’d like clarification regarding displaying ads on your web page that contains ads associated with another Google AdSense publisher. If your website is in compliance with our program policies (http://www.google.com/adsense/policies ) and you give others permission to display ads on your site, they may place their ad code along with other publisher’s ad code on the same page. You will, however, need to give permission to all those wishing to display ads on their website."
... You guys have no idea? Thanks for that Lordy. You obviously got that response from a lame Googler. You might like to refer to their Online Standard Terms and Conditions. I draw your attention to section 2, the sub-section on AdSense for Content. It states: "You agree that while You may display more than one (1) Ad Unit on each Site Web page, You shall not display any Ad Unit on a page that contains Ads associated with another Google AdSense customer (e.g., Your Web hosting company), unless authorized to do so by Google." My bold. That's the letter of law that the majority go by.
Actually, no, you're both half wrong, but if you combine what you both said you've got it. You actually quoted the relevant portion CountryBoy: "unless authorized to do so by Google." What he got was that authorization... and Lordy, without writing to them and having them reply back that it's ok, then no, it's not legal. -Michael