…A majority of members of the European Parliament voted in support of amendments to the bill that would make it harder to register a patent. The amendments tightened up the wording of the bill to make it explicit that no patent, like the one Amazon.com registered for its one-click online shopping method, can be registered in the union. Such patents are known in the industry as business-method patents.

The members of Parliament also expressly outlawed patents for algorithms, the mathematical equations in software programs, and they restricted the definition of the sort of software that should be eligible for a patent.

"We have rewritten this law," said Arlene McCarthy, a Socialist Party member of the European Parliament from Britain, who was instrumental in forging the Parliament's position on the law.

"We are sending a clear message that the Parliament wants strict limits on patentability for software," she said, adding that the version of the bill agreed upon today balanced the need for a unionwide legal regime that allows inventors to protect their inventions, with the need to avert a European move toward the more protective patent laws in the United States.

The lobbying effort behind the bill has been intense. Several members of Parliament, including Ms. McCarthy, accused opponents of software patents of being aggressive in promoting their view.

Open-source and free-software advocates, as well as some economists, have been pushing hard and loud for the bill to be scrapped, arguing that software developers do not need the protection of patents. They argue that software development occurs incrementally, so that by patenting an idea and preventing another engineer from developing that idea further, patent laws put a brake on innovation.

Patents, they contend, pose more of a threat than a help to small companies of software developers. "As a small firm you go unnoticed by the big software makers until you create something really special," said Robert Dewar, president of Ada Core Technologies, a small company that is based in New York.

"Then you start to receive letters from patent lawyers representing big firms that either want to buy a license to your software at a cheap price, or they simply want to drive you out of business so they can pick up your idea for next to nothing in the bankruptcy court after you have been sunk by astronomical legal fees," Mr. Dewar said.