But the deal edged a bit closer as a Federal Court 2011 ruling in an anti-trust suit brought against Nielsen was upheld in appeal. The 2011 decision found that while Nielsen was a monopoly in the US TV ratings business, it wasn't behaving in an anti-competitive manner. That finding was just confirmed on appeal.
“Neither party disputes that Nielsen exercises monopoly power over the television audience measurement services industry, both nationally, for the United States as a whole, and for all 210 markets.”However, the court ruled that on the specific allegations of the suit - that Nielsen had acted to prohibit other audience measurement services from entering the Miami market - that there was no evidence of specific anti-competitive behavior. If such evidence had been forthcoming, it would likely have had a significant impact on the FTC's ruling of whether the Nielsen-Arbitron deal would be anti-competitive.
Another factor in Nielsen's favor is that while Nielsen and Arbitron had once been fierce competitors in the U.S. TV and Radio ratings business, there is limited direct competition between the two today.
From 1978-1989 as Arbitron went head-to-head with Nielsen in the local TV ratings business, 60% to 80% of clients subscribed to both, the appeals court said. Those days are long gone -- Arbitron pulled out of that arena in 1993 -- much to the dismay of many in the advertising business.As such, the purchase of Arbitron is seen primarily as a way for Nielsen to expand into additional areas of audience behavior measurements, and not as a means to remove a rival. If that perception holds true, the FTC could still approve the deal, even if Nielsen is technically a monopoly.
Source - Confirmed: Nielsen Is A Monopoly -- But Court OK With It, TVBlog