* U.S. appeal court affirms patent ruling against CSR
* CSR says could face further litigation
* CSR shares fall 1.7 percent
(Adds details, shares, analyst comment)
LONDON, April 13 (Reuters) - A patent lawsuit between chipmakers Broadcom BRCM.O and CSR CSR.L will resume after a U.S. appeal court ruled against CSR in a case involving GPS navigation chips, CSR said on Tuesday.
UK-based CSR — which makes wireless chips for customers including Nokia NOK1V.HE, Apple (AAPL.O) and BlackBerry maker Research in Motion RIM.TO — also said it might face further litigation from Broadcom or others.
“We will continue to take appropriate steps to deal with any claims that may be made,” CSR said in a statement.
CSR shares fell 1.7 percent to 436 pence by 0809 GMT, underperforming a flat wider market. Goldman Sachs also cut its price target on the stock to 525 pence from 550 pence on unrelated margin concerns.
The lawsuit concerns SiRF, a U.S. company that CSR bought a year ago, and predates the acquisition.
The U.S. Court of Appeals for the Federal Circuit on Monday affirmed a year-old ruling by the U.S. International Trade Commission that SiRF had infringed on three Broadcom GPS patents, and banned the import of the infringing chips.
SiRF has since redesigned the global positioning-system (GPS) chips in question, and these have been imported for consumption and sale in the United States.
“We believe this appeal was simply an attempt by SiRF to restore its reputation,” analysts at Citi said in a note.
CSR said that as a result of the ruling a 2006 patent case between SiRF and Broadcom, in which each is asserting patents against the other’s products, would come unstayed and proceed. (Reporting by Kate Holton and Georgina Prodhan; Editing by Louise Heavens)