Aereo is warning of “grave” harm to its operations as it appeals a federal court’s order that it shut down its Salt Lake City and Denver, a move that offered broadcasters a significant victory as it tries to halt the unauthorized digital streaming of station signals.

In a series of legal maneuvers late on Wednesday and early on Thursday, Aereo asked U.S. District Judge Dale Kimball to stay his decision that the startup halt its operations throughout the 10th Circuit, which covers Utah and Colorado and four other western states, as it seeks its appeal.

Kimball sided with broadcasters’ contention that Aereo was violating the Copyright Act because its streams of broadcast signals to digital devices were public performances. His decision marked the first victory for the broadcasters in federal court, after judges in New York and Boston have so far ruled in Aereo’s favor and refused to halt its service.

In a brief to Kimball, Aereo argues that the potential harm to its operations extends beyond the markets in the 10th Circuit where it has launched. It began offering service in Denver and Salt Lake City last year.

“A preliminary injunction would cause great and permanent harm to Aereo and to thousands of members of the public as soon as it takes effect,” Aereo said. “An injunction will cause great confusion in the minds of the general public on the basic legality of using a remote antenna to access free-to-air broadcast content and to make a personal copy of that broadcast content on their remotely located DVR, even in jurisdictions where the courts have explicitly endorsed Aereo’s legality. Consumers in this district who have signed up for Aereo, paid fees, and purchased devices (such as iPads) will be significantly harmed if they can no longer access over-the-air broadcast television with an Aereo antenna and DVR.”

The Supreme Court will hear oral arguments on April 22 in the broadcasters’ challenge to lower court rulings in New York that upheld the legality of Aereo. The startup argues that the the fact that the high court is hearing the case “demonstrates the significance of the legal issue and weighs heavily in favor of staying the preliminary injunction.”

“The damage to Aereo itself would be tremendous,” the company said. “Aereo will continue to pay for its fixed costs. Additionally, Aereo has spent significant resources entering into these markets.” It also argued that waiting for a Supreme Court ruling would not harm broadcasters, even though Kimball found that broadcast stations were suffering harm because it would undermine their ability to negotiate for the transmission of their signals, among other factors.

Broadcasters’ opening briefs to the Supreme Court are due on Monday, and it is likely that they will cite the victory in Utah to bolster their claim that other federal court rulings were outside the norm when it comes to the interpretation of the Copyright Act.