The debt rating company says that several broadcasters who have taken Aereo to court probably will defeat its new effort to sell customers a streaming service for over-the-air signals. The courts will agree with the plaintiffs who say that the effort violates their copyrights. Aereo says that it’s just offering remote access to the kinds of services consumers can already get at home using an antenna, DVR, and a Slingbox. If Aereo were to prevail, Moody’s Investors Service says, then it would be a serious blow to some of the media business’ largest companies. It could undermine broadcasters’ ability to demand retransmission consent payments from pay TV providers. (Why should they pay if Aereo can retransmit local station signals for free?) And if lots of people liked Aereo’s $12 a month service — which also offers the ability to record up to 40 hours of programming and replay it on demand, much like a DVR — then “it would also jeopardize (broadcasters’) advertising revenue.” Ratings services including Nielsen “do not currently have the capability of capturing online viewing accurately.” Cable has less to fear from Aereo: It would mostly appeal to viewers “who already don’t have cable” or who want to watch TV on mobile devices. Although it could compete with cable and satellite TV Everywhere initiatives, Aereo might not provide a big incentive for consumers to cancel their pay TV service. The ranks of cost-cutters “primarily consist of a young demographic that asn’t yet transitioned into household formation where TV viewing is more ubiquitous, or those who are doing without cable as result of tough economic times.” Aereo launched this week in New York City, although its case is still before the U.S. District Court.