Two former employees of Kaspersky Lab have accused the malware protection software company of seeding competitors’ products with fake malware signatures intended to make them erroneously label benign files on customers’ computers as malicious. The allegations, made in a report published by Reuters Friday morning, have been strongly denied by a Kaspersky Lab spokesperson.

According to Reuters, the “junk” files were tailored to have the same signature as legitimate files, based on the fingerprinting mechanisms of competitors’ products. To do this, the two former employees alleged, Kaspersky assigned employees to reverse-engineer competitors’ products to see how they identified malware and then tailored samples that would match the signatures of common, harmless files.

The report does not include many specifics about the alleged faked signatures, such as which files were targeted for identification as false positives.

While there have been incidents reported by Microsoft, Symantec, and others of attacks by outside parties aimed at creating false positives by submitting “junk” files as malicious, none had publicly suspected Kaspersky of creating them. Microsoft's Dennis Batchelder and Hong Jia reported such attacks in a presentation at the Virus Bulletin conference (PDF) in October 2013. The files were in some cases widely shared by antivirus vendors, and some were submitted anonymously over the Tor network.

Liam O’Murchu, a reverse engineer and security researcher at Symantec, acknowledged similar attacks on Symantec’s products in a post to Twitter, saying, “We had investigated these attacks but could not find out who was behind them. We had some suspects, Kaspersky was not one of them.”

According to the two former employees cited by Reuters, Kaspersky Lab employees have been spreading these types of faked malware fragments for the past decade as part of a campaign to undermine competitors’ malware protection tools, in some cases at the direct order of cofounder Eugene Kaspersky. One of the former Kaspersky Lab employee told Reuters that Kaspersy felt that some malware providers were too closely copying Kaspersky Lab’s software, and “Eugene considered this stealing.” Company researchers were assigned for months at a time to reverse engineer competitors’ software to determine how to trick them into falsely identifying good files as potential malware, according to the Reuters report.

If true, this isn’t the first time Kaspersky has used fake malware files to fool others. Kasperky Lab had previously performed an experiment similar to the “paper towns” approach used by road atlas makers to protect their work. In 2010, Kaspersky Lab analyst Magnus Kalkuhl announced that the company had, as an experiment, created 10 harmless files and told the tracking site VirusTotal—which aggregates data on malware files—that it considered them malicious. The files were posted to see if competitors were improperly copying Kaspersky’s research work; within a week and a half, Kalkhul reported at the time, 14 companies had also labeled the files as malicious.

"In some cases the false detection was probably the result of aggressive heuristics," Kalkhul wrote in a blog post about the experiment, "but multi-scanning obviously influenced some of the results. We handed out all the samples used to the journalists so they could test it for themselves. We were aware this might be a risky step: since our presentation also covered the question of intellectual property, there was a risk that journalists might focus on who copies from whom, rather than on the main issue (multi-scanning being the symptom, not the root cause) But at the end of the day, it’s the journalists who have it in their power to order better tests, so we had to start somewhere."