The two firms met recently with Resolutions, a firm specialising in mediating corporate disputes, to try and settle the antitrust row between them but a Nielsen spokeswoman told Research that the “session did not produce a resolution”.

“We are now waiting to hear the next step from the court,” she said.

The wrangle between the two firms kicked off last year when Sunbeam launched antitrust proceedings against Nielsen, claiming that the ratings company had abused its monopoly position and that its audience figures and ad revenue in the Fort Lauderdale and Miami markets had been damaged by the introduction of local people meter technology.

Nielsen described the allegations as “utterly without merit” and has twice had them dismissed, although the court allowed Sunbeam to file an amended complaint on both occasions.

Sunbeam’s last complaint was filed in January this year, and Nielsen again moved for dismissal in March.