Inject advertisements in pages

Question

Today I noticed that in the Chrome web store dashboard, under my extension's settings there is a check-box labeled "Ads Behavior", and whose description is "This extension injects ads into some third-party websites.".

My questions are:

• Can an ad-supported extension inject advertisements in a page visited by the user?
• If so, what is an acceptable policy?
• Can the extension replace existing advertisements (even though that seems to me kind of unethical/stealing) or must it only create new ones?
• Is it possible to use any ads network or must it be adsense?

Thanks

Answer 1

Is it possible to use any ads network or must it be adsense?

Actually it can't be AdSense. It's specifically mentionned in their program policies:

Currently, we don't permit Google ads or AdSense for search boxes to be distributed through software applications, including but not limited to, toolbars, browser extensions and desktop applications.

I wonder if any ad provider allows such a thing.