Judge Paul Huck has given the research firm a deadline of 25 March to respond to the broadcaster’s claims.

Sunbeam alleges that the introduction of Nielsen’s local people meter (LPM) technology as the TV measurement tool for the Miami/Fort Lauderdale market has harmed its viewing figures – costing it more than $1m each month in lost advertising revenue.

It claims that Nielsen used its position as a “monopoly” to force LPMs on the market, despite objections from TV companies, and that its staggered, long-term contracts prevent competitors coming to market and offering an alternative measurement system.

Nielsen argued in its motion for dismissal that Sunbeam had failed to allege that potential competitors were excluded from the Florida market, but Judge Huck said the court was “satisfied” that Sunbeam had done so.

Sunbeam first launched its action in May 2009. Its complaint has been dismissed twice, but each time the court granted the firm leave to amend.