Three Utah broadcasters and Fox have filed suit against Aereo in Utah, challenging the legality of the startup’s offering of digital streams of broadcast signals.

The suit, filed on Monday, is the latest litigation against Aereo, which launched in New York City in March 2012 and in Salt Lake City in August.

Plaintiffs KSTU-TV, KUTV-TV, KMYU-TV and the Fox Broadcasting Co. contend that Aereo’s service violates the public performance clause of the Copyright Act. Aereo has contended that its service is legal, as subscribers are each assigned a tiny, dime-sized antenna and are, in essence, in control of their viewing experience.

In a statement, the plaintiffs said that “no amount of technological gimmickry by Aereo changes the fundamental principle of law that those who wish to retransmit copyrighted broadcasts may do so only with the copyright owners’ authority.”

Stations have so far been unable to shutdown Aereo’s service in New York, after a district court and appellate court refused to issue a preliminary injunction to end the digital feeds, That case is now in the discovery phase on its way to trial, and Fox has said that it may appeal to the Supreme Court if necessary.

Also pending is a decision from a federal judge in Boston on Aereo’s service there. At a hearing last month, the judge said that he was inclined to deny stations’ request for an injunction, but it was not a final ruling.

Aereo launched on Aug. 19 in Salt Lake City, promoting itself as offering “Live TV Online.” In their complaint, the broadcasters say that by capturing, reprocessing and copying their signals for delivery to subscribers, Aereo falls under the definition of a public performance because it is transmitting to a base of customers. Aereo has contended that its service is a private delivery and not a public performance.

In a statement, Aereo spokeswoman Virginia Lam said that the “fact that Fox did not prevail in their efforts to enjoin Aereo in their existing federal lawsuit does not entitle them to a do-over in another jurisdiction. All this meritless suit amounts to is forum shopping, and we are hopeful that any such efforts to commence duplicative lawsuits to try to seek a different outcome will be rejected by the courts.”

Also on Monday, a magistrate judge in New York ruled that Aereo CEO Chet Kanojia and its chief technology officer, Joseph Lipowski, had to submit to depositions about the company’s patents. In the New York litigation, broadcasters are trying to establish that Aereo’s technology is not based on equipment that consumers could otherwise buy themselves.