Report: Comcast Under Investigation

Comcast is being investigated by the U.S. Department of Justice over whether its business practices violate federal antitrust law, according to a report Wednesday by the Wall Street Journal.

The focus of the investigation is Comcast's behavior in the spot cable ad-sales business.

The government, according to the report, is "probing whether Comcast's cable ad sales practices, as well as its deals to represent rival pay-TV providers' ad sales, are hindering competition."

Comcast vowed to cooperate with the investigation.