The Internet TV service YouView has lost a High Court appeal over the use of its name.
The YouView brand was found to be "confusingly similar" to Total Ltd's "Your View" trademark.
Total Ltd is a telecommunications company based in Gloucestershire. It opposed the use of YouView's name when it applied to the Trade Marks Registry, and on Friday YouView lost its appeal against the original decision.
The ruling could mean further court proceedings that could lead to an infringement action that could eventually limit the use of the trade mark.
But YouView remained defiant after the ruling and said it had no intention of changing its name.
A spokesperson said: "YouView has no intention of changing its name. This matter is complex and subject to a number of on-going legal actions and will be settled in the courts."
Meanwhile the director of Total said that the company's opposition had been "vindicated".
He said after the ruling: "We are delighted with the judgment. YourView is a key differentiator for us and is a significant part of our business and future growth strategy, so it was absolutely imperative that we defended the trade mark that was granted to us in 2009."
YouView, for which Lord Alan Sugar acts as chairman, was co-founded by the BBC, ITV, Channel 4, TalkTalk, BT and Channel 5. It provides free access to Freeview and on-demand services via a dedicated, internet-enable set-top box.
It launched after many delays in July 2012 for £299. It is also available for free from TalkTalk and BT with their broadband deals. It is not known how successful it has been, though TalkTalk said it had given away 29,000 boxes.