As of this week, no more advertisements incorporating "sexually explicit content" will be promoted by Google's advertising network.
Google's AdWords platform is used to place advertisements on Google-owned sites; other sites can also choose to host AdWord ads on their own sites. The platform is thought to be responsible for the majority of Google's revenue, but although Google has placed restrictions on adult content for a while, the latest changes could potentially have chased some advertisers elsewhere.
According to CNBC, Google sent a message to advertisers at the beginning of June in order to notify them that it will no longer accept ads "that promote graphic depictions of sexual acts." It went on to say that this included content such as hardcore pornography and the depiction of masturbation and genital, anal, and oral sexual acts.