SAP has filed a court action against patent holder Pi-Net International, which it says has filed patent infringement lawsuits against a number of SAP customers.

The alleged infringements, which concern three Pi-Net patents, are associated with SAP's Financial Fusion software, which is used for online banking and other purposes. SAP gained the software through its 2010 acquisition of Sybase.

At least one SAP customer has asked the vendor to indemnify it against any liabilities that could ensue from Pi-Net's lawsuits, according to SAP's filing in the US District Court for the Northern District of California.

SAP is seeking a declaratory judgment stating that its products don't infringe on Pi-Net's patents, a move that would shield both itself and customers from litigation.

The three patents in question cover "multimedia transaction services," "web application network portal" and "value-added network system for enabling real-time, bi-directional transactions on a network," according to SAP's suit.

Some evidence suggests Pi-Net is a so-called non-practising entity, placing more effort on enforcing its intellectual property rights in search of licensing fees and damages, than creating products for sale in the market.

Pi-Net does not appear to have a dedicated website, but a phone number listed for the company is also associated with the Menlo Park, California, firm WebXchange.

The latter company's website contains a description for a product called Transweb that "intelligently routes, switches, tracks, and manages value-added internet transactions."

WebXchange's software was beta-tested at Cisco and put into use at First Data, according to the site.

Another page describes WebXchange as an "aggressive startup" and lists job openings for software engineers.

However, it was not clear how current or accurate the information on the dated-looking site was at the end of last week, as a copyright notice on one page is labelled 2007.

In 2010, WebXchange and Pi-Net's founder, Lakshmi Arunachalam, filed an amicus curiae brief in a patent case brought against Facebook by Leader Technologies. Such briefs allow third parties to weigh in about information relevant to a case.

The brief describes her as "the inventor of a portfolio of the earliest internet patents that give control over any real-time web transaction from any web application."

In addition, "these patents give her control over the internet cloud and any cloud application," according to the brief, which also asserts that Pi-Net and WebXchange are "practicing [sic] entities with the earliest products implementing web applications based on her patents."

"Arunachalam invests 100% of her time in research and development (R&D) and in the patenting of new internet-based products," it adds.

Court records and news reports show that WebXchange has sued other tech vendors in recent years for patent infringement, including Dell and Microsoft.

Records also show that Pi-Net has filed lawsuits against a series of financial institutions within the past year or so, including Merrill Lynch and Bank of America. It wasn't clear whether these were among the SAP customers referred to in SAP's filing, which were not named.