HELSINKI, March 2 (Reuters) - Patent holder IPCom GmbH said a German court had ruled on Wednesday that one of its patents being disputed by international phone makers and telecoms operators was valid.

Phone makers Nokia (NOK1V.HE), HTC (2498.TW), and telecom operators T-Mobile and Vodafone (VOD.L) were seeking to overturn IPCom's patent 173, which is instrumental in handing calls between base stations.

Nokia was not immediately available for comment.

IPCom owns the mobile telephony patent portfolio created by Bosch [ROBG.UL] between the mid-1980s and 2000, which includes about 160 patent families worldwide, including some of the key patents in wireless space.

On Feb. 18, IPCom enjoyed another court victory, with a ruling that Nokia had infringed its patent 100, which standardises cellphones' first connection to a network.

IPCom said it had "been approached" after that ruling by a company it declined to name, with a view to licensing its patents. (Reporting by Tarmo Virki; Editing by Will Waterman)