A fight has erupted in Congress over the question of whether companies should be allowed to keep patents they obtained by misrepresentation or cheating, The New York Times reports. And the issue has emerged as a contentious point in legislation to overhaul patent laws.

In several cases, the courts have voided patents after finding that companies intentionally misled the Patent and Trademark Office. Federal judges can void patents after finding a company engaged in “inequitable conduct,” a reference to misrepresentation or info that was concealed with an intent to deceive the patent office. In such cases, judges can declare the patents unenforceable.

“This is like imposing the death penalty for relatively minor acts of misconduct,” Bob Armitage, Lilly’s senior vp and general counsel, tells the paper. As his remark indicates, brand-name drugmakers are urging Congress to eliminate the penalty, or to curtail it as proposed under a bill passed by the House.

But Debra Barrett, a Teva Pharmaceuticals vp, tells the Times that the changes sought by brand-name drugmakers “would make it easier for them to cheat and get away with it, easier for them to defend their patents and more difficult for us to get generic products onto the market in a timely way.”

The House has approved a comprehensive patent bill that would make it harder to prove inequitable conduct, the Times writes. Senators are haggling over a companion bill, approved by the Senate Judiciary Committee, and hope to take it to the floor this summer.

In the last 15 years, the US Court of Appeals for the Federal Circuit, which handles patent cases, has affirmed findings of inequitable conduct in at least 40 cases, including 14 that involved drug or health care products, the Times writes. Similar findings have been issued by federal district judges in an unknown number of cases that were not appealed.

Courts have found that drugmakers knowingly submitted false statements to the patent office, inaccurately described experiments and concealed info that contradicted their claims, the paper notes.

In one case, the appeals court said Novo Nordisk improperly failed to disclose that it hadn’t performed an experiment described in its application for a patent related to synthetic human growth hormone. In another case, the court said Pharmacia, now owned by Pfizer, had used an “inaccurate and misleading” affidavit in obtaining a patent for a glaucoma med, according to the Times.

Brand-name drugmakers say that generic drug makers routinely attack their patents by accusing them of inequitable conduct when they are blameless or guilty of no more than honest mistakes. The aggressive use of such accusations has become “a plague on the patent system,” the Biotechnology Industry Organization, a trade group, told Congress.

In reviewing an application, patent examiners can search the relevant literature, but may not find all the pertinent information, so they depend on applicants to be forthright, the Times writes.

“If Congress eliminated or reduced the penalty for inequitable conduct, applicants would no longer have a reason to disclose all the information they are aware of,” Robert Budens, president of the Patent Office Professional Association, which represents 5,500 examiners, tells the Times.

“The doctrine of inequitable conduct is used so aggressively in litigation that it has unintended consequences. Applicants give the Patent and Trademark Office too much information, to avoid allegations that they concealed anything, and they refuse to explain the information, to avoid later allegations that they engaged in some form of misrepresentation,” Lilly’s Armitage tells the paper.