In Chrome, any extension hosted in the Chrome Web Store must comply with the Developer Program Policies. These require that extensions have a narrow and easy-to-understand purpose. We don’t ban injectors altogether—if they want to, people can still choose to install injectors that clearly disclose what they do—but injectors that sneak ads into a user’s browser would certainly violate our policies. We show people familiar red warnings when they are about to download software that is deceptive, or doesn’t use the right APIs to interact with browsers.
On the ads side, AdWords advertisers with software downloads hosted on their site, or linked to from their site, must comply with our Unwanted Software Policy. Additionally, both
Google Platforms program policies and the DoubleClick Ad Exchange (AdX) Seller Program Guidelines, don’t allow programs that overlay ad space on a given site without permission of the site owner.
