The three largest groups in the European Parliament have decided to conditionally show their approval of a controversial patent agreement, in a move that is likely to have a significant effect on the future of European software patent policy.

In a draft resolution agreed upon this week, the conservative EPP-ED, the social democratic PES and the libertarian ALDE agreed, among other things, said the controversial European Patent Litigation Agreement (EPLA) was worthy of further discussion, while noting particular reservations.

The EPLA proposes to make drastic changes to the way patents are enforced in the EU, setting up unified bodies such as a European Patent Court. Currently national courts enforce different rules across the region.

Critics say the agreement would take patent issues out of the hands of the democratically elected European Parliament and would make software patents strongly enforceable in Europe. Such criticisms led the EP to scrap a proposed patent directive last year, despite strong backing from the European Commission and large multinationals such as IBM and Microsoft. More or less the same groups are now backing and opposing the EPLA, according to industry observers.

Parliamentary groups such as PES, Greens/EFA, GUE/NGL and IND/DEM have strongly criticised the EPLA in recent days and had wanted to pass a resolution clearly condemning the agreement. By contrast, groups such as EPP-ED and ALDE wanted to unequivocally support the EPLA.

The compromise means the parliament will give conditional support to further developing the EPLA, urging the Commission "to explore all courses for improving the patent and patent litigation systems in the EU, including participation in further discussions on EPLA".

However, it notes that "the proposed text needs significant improvements and a satisfactory proposal for the Rules of Procedure of the EPLA Court".

The three groups have a strong majority of the parliament's 732 seats, so the resolution is unlikely to face a challenge in next week's vote. The EPLA is expected to take at least another two years to finalise, if it is ever passed.

The resolution isn't a knockout blow for those opposed to European software patents, but it isn't a Christmas present, either, according to anti-software patent activist Florian Mueller. "We would have needed a clear decision in our favour a little more than the others. That's life," he wrote on his blog. "We can definitely live with this outcome."

He said the resolution should serve as "a wake-up call" that software patents are far from a dead issue in the EU. "The EP is now going to say Maybe, but… instead of No to a proposal that, among other things, would make software patents strongly enforceable in Europe," he wrote.

Software patents have been at the root of several high-profile, disruptive court cases in recent months, including lawsuits against RIM and Microsoft. In general, however, they are used by large companies to compel smaller companies to pay licensing fees, ensuring that the barriers to competition remain high.