Cervelo Cycles has taken legal action to defend itself against Canyon Bicycles' suit.
Last year Canyon filed suit against Cervelo, alleging that the older R-series seattube infringes on its patents.
Cervelo has taken action to defend its designs - and the firm is also opposing the patent at the European Patent Office.
Cervelo said in a statement: "Cervelo has taken action to defend our designs and is also opposing the patent at the European Patent Office on grounds including lack of novelty and obviousness.
"The European Patent Office hearing on the validity of the patent has not yet taken place. In the meantime, there have been initial decisions in the German court, partially favorable to Cervelo, partially favorable to Canyon. We are appealing this court decision and at the same time we feel we have a very strong position against the patent in the Patent Office hearing, scheduled for November 2010.
"Sales of the older R-models will continue uninterrupted. The dispute is limited to these older R-models; the completely new 2011 R-models with the BBright innovation are not affected."