In my experience working with large media content sites, the advertiser does not have any sort of "sign off" but they do want to make sure the content is in-lin

In my experience working with large media content sites, the advertiser does not have any sort of "sign off" but they do want to make sure the content is in-line with what they paid to sponsor. The leverage comes from the fact that if the advertiser doesn't like the final output, the dollars move elsewhere next quarter.