The News Corp.-owned network sent Cablevision a cease-and-desist letter Tuesday accusing the company's service reps of making false claims about Fox as they try to persuade subscribers not to jump to competing TV services.
Fox also said Cablevision has been directing its customers to websites that carry Fox shows in violation of copyright laws.
Fox has been dark for Cablevision subscribers since Oct. 16. The companies continue to argue over how much Cablevision should have to pay to carry Fox on its lineup. These types of disputes have become more common as broadcasters look for higher rates.
Cablevision responded to Fox's letter Tuesday by accusing the network of trying to distract from the blackout, which may now cut into the World Series games.
The series starts Wednesday between the San Francisco Giants and the Texas Rangers.