(BREITBART) AppNexus Inc., operator of one of the biggest digital advertising services, has barred Breitbart News from using its ad-serving tools because the conservative online publisher violated its hate speech rules.

AppNexus scrutinized Breitbart’s website after U.S. President-Elect Donald Trump tapped Steve Bannon, former executive chairman of Breitbart, to be White House chief strategist last week. The digital ad firm decided the publication had breached a policy against content that incites violence, said AppNexus spokesman Joshua Zeitz.

“We did a human audit of Breitbart and determined there were enough articles and headlines that cross that line, using either coded or overt language,” he said.

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