It’s not uncommon for TV networks and pay-TV operators to get into very public spats about contract negotiations and looming blackouts, but the folks at Dish say that NBCUniversal crossed the line this week in going public about its ongoing contract dispute with the satellite company.

According to a lawsuit [PDF] filed by Dish today in a federal court in Illinois, NBC’s contract with the satellite company prohibits the network from “engaging in certain public communications and/or messaging that relate to the expiration of these agreements.”

But as millions of Dish customers have seen in recent days, NBC has been anything but silent on the possible blackout of multiple channels — including NBC, Telemundo, USA, Syfy, Bravo, CNBC, and MSNBC.

In addition to running ads, posting alerts on social media, and putting anti-Dish messaging in a text screen crawl on NBC-owned stations, the network recently launched a website calling on viewers to “demand they keep your shows!”

“The parties agreed to prohibit NBCU from engaging in these kinds of public communications because they cause actual harm to DISH,” reads the complaint. “Among other things, DISH’s subscribers flood DISH’s customer services lines with questions about the NBCU messages, some subscribers cancel their DISH subscriptions, and DISH’s goodwill as a reliable service provider is eroded. These material breaches of the contacts are not capable of being cured, among other reasons, because once a customer changes service providers, DISH cannot get them back.”

Dish acknowledges in the suit that its contract with NBC does allow for the network to make some public statements about pending blackouts when contracts “are set to expire in less than seventy-two hours.” However, Dish says the agreement explicitly prohibits even these messages from including “negative language about DISH, a call to action, or any information regarding the negotiation or expiration of the Agreements.”

In a statement regarding the lawsuit, Dish also contends that, as a condition of the 2010 merger of Comcast and NBC, the network is blocked from blacking out its networks if a pay-TV provider chooses enter into binding arbitration, and Dish says it intends to exercise its right to do so. The NBC-owned channels would stay on Dish pending the outcome of that arbitration, according to the satellite service.

UPDATE: In a statement emailed to Consumerist, a rep for NBCUniversal writes, “Should Dish proceed with arbitration we will of course participate in the process, and look forward to receiving the fair market value for our portfolio of networks.”

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