Google is no longer allowing the advertising of sexually explicit content on its network.

A report from Chris Morris at CNBC says the changes went into effect on Monday, and that earlier in June, Google sent those who were about to be in violation an email that said:

Beginning in the coming weeks, we’ll no longer accept ads that promote graphic depictions of sexual acts including, but not limited to, hardcore pornography; graphic sexual acts including sex acts such as masturbation; genital, anal, and oral sexual activity.

When we make this change, Google will disapprove all ads and sites that are identified as being in violation of our revised policy. Our system identified your account as potentially affected by this policy change. We ask that you make any necessary changes to your ads and sites to comply so that your campaigns can continue to run.

Google actually announced the changes in its help center in March:

The AdWords policies on adult sexual services, family status, and underage or non-consensual sex acts will be updated in late June 2014 to reflect a new policy on sexually explicit content. Under this policy, sexually explicit content will be prohibited, and guidelines will be clarified regarding promotion of other adult content. The change will affect all countries. We made this decision as an effort to continually improve users’ experiences with AdWords. After the new policy goes into effect, the adult sexual services, family status, and underage or non-consensual sex acts policy pages will reflect this change.

Still, according to the CNBC, some advertisers were caught off guard. Perhaps that wasn’t the most visible place to announce such a change.

You have to wonder how much ad revenue Google is sacrificing by changing its policy.