The Supreme Court on Wednesday declared that internet TV service Aereo violates copyright law, in a closely-watched case that may have long-term implications for both the TV and cloud computer industries.

In a 6-3 opinion, Justice Stephen Breyer wrote that Aereo infringed on broadcasters' exclusive right to transmit their programs over-the-air, and that the start-up engaged  in an unlicensed public performance. Breyer concluded that Aereo was more similar to a cable company and not, as Aereo claimed, like a modern day VCR:

In sum, having considered the details of Aereo's practices, we find them highly similar to those of the CATV systems in Fortnightly and Teleprompter. And those are activities that the 1976 amendments sought to bring within the scope of the Copyright Act. Insofar as there are differ- ences, those differences concern not the nature of the service that Aereo provides so much as the technological manner in which it provides the service. We conclude that those differences are not adequate to place Aereo's activities outside the scope of the Act.

Aereo, which launched in 2012, rattled broadcasters with its service that let subscribers pay $8/month to capture and record free over-the-air TV signals, and play them on their computers or on mobile devices.

The ruling means that Aereo, which operates in about a dozen cities, will have to wind down its operations almost immediately, and its investors, led by media mogul Barry Diller, will have to walk away from the nearly $100 million they have put into the company.

Justice Antonin Scalia wrote the dissent, joined by two other conservative justices, arguing that Aereo did not "perform" at all -- an interpretation of the law that enjoyed considerable support by many law professors.

We'll have more soon. In the meantime, here's further background:

The question at the heart of the case turned on the tiny antennas that Aereo rented to each subscriber. The company argued that they were like a private rooftop antenna attached to a VCR, while broadcasters described the set-up as a "Rube Golderg" device to mask copyright infringement.

Broadcasters and sports leagues feared that a win by Aereo would lead cable companies to rejig their services in an attempt to avoid paying so-called retransmission frees. Meanwhile, many big tech and internet companies supported Aereo, warning that an adverse ruling could threaten the legal status of popular consumer cloud services like Dropbox and Google Drive.

When the Supreme Court heard the case in April, the Justices appeared to be struggling with how to take account of the interests of content owners without threatening the emerging cloud computer industry.