Motorola has won a patent infringement battle against Microsoft over its video compression software that could result in Windows 7 being withdrawn from sale in Germany.
The ruling, which also covered Microsoft's Xbox console, is the latest in one of the many long-running patent battles taking place between the world's largest tech firms.
Microsoft had previously taken the precautionary step of moving its software distribution centre from Germany to the Netherlands.
It had also won a court order in the US prohibiting Motorola from enforcing any sales ban won in the German courts.
The German judge said that video compression software in use within Windows 7 and the Xbox, known as H.264, infringed on patents owned by Motorola and ordered the firm to remove its products from sale, according to a report on Reuters.
Motorola welcomed the decision from the court and said it hoped the matter could be resolved in due course.
"As a path forward, we remain open to resolving this matter. Fair compensation is all that we have been seeking for our intellectual property," they said.
Microsoft said it remained confident it would see off the legal challenge from Motorola and force the firm to adhere to its prior promises relating to the use of its patents within its products.
"This is one step in a long process, and we are confident Motorola will eventually be held to its promise to make its standard essential patents available on fair and reasonable terms for the benefit of consumers who enjoy video on the web," it said.
"Motorola is prohibited from acting on today's decision, and our business in Germany will continue as usual while we appeal this decision and pursue the fundamental issue of Motorola's broken promise."
Microsoft has hit out at Motorola in the past over its tactics with relation to video compression H.264 software, claiming it is asking for fees far in excess of what is reasonable within the market and what it charges for the use of its patents.
The firm has also sided with Apple, and several other firms, to complain to the European Commission about Motorola's tactics in light of its acquisition by Google for $12.5bn, which has been approved in the region and is set to be finalised in the coming months.
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