Earlier quoted context omitted.
> Even if the search result and some ads were provided by Google, requiring exclusivity for search adverts was too much. Which completely ignores why ad networks have those restrictions. At one point it was common for crummy web pages to sign up for every ad network. All of them. Because every one you signed up for was more money. Then the whole side of the page would be ads from different networks. The obvious probl…
If an ad network wants to put restrictions on the volume of ad space in comparison with content on the page, they can do so, but requiring exclusivity isn't the same thing as that.
Even trying to price just based on how many other ad networks there are is problematic. For each additional ad network the value of each ad goes down. Even adding a second one may cut the value more than in half compared to exclusivity, because if the user sees the other network's ads first and they don't appear relevant they may not even look at yours, and a user who sees a larger number of ads may not look closely at any of them.
If the price offered for any non-exclusive placement is more of a reduction over the price offered for exclusivity than the amount gained from the other ad network(s), how is that any different in practice than requiring exclusivity?