Malwarebytes is extending an olive branch to software pirates as it tries to banish bogus licenses from its system.

The company’s Amnesty program flags potentially pirated versions of Malwarebytes Anti-Malware Premium, and offers a legitimate year’s subscription (normally $25) in exchange. Legitimate users who’ve been mistakenly flagged as pirates can also ask for a longer subscription—or even a lifetime license—to match their original purchase.

As Malwarebytes CEO Marcin Kleczynski explained in the company’s forums, many years ago the company made the mistake of using an insecure licensing key algorithm. This made it easy for pirates to generate their own keys, and for unscrupulous vendors to sell false licenses. As Malwarebytes’ user base has grown, this has led to bogus keys overlapping with legitimate ones.

Malwarebytes is now switching to a more secure licensing system, but in the process must deal with all those duplicate keys. The Amnesty program is designed to let legitimate users (and users who thought they were legitimate) request fresh licenses while attempting to convert some pirates in the process. Malwarebytes says the old keys will stop working “after a period of time.”

Some users in Malwarebytes’ forums have pointed out that it’s entirely possible for pirates to claim that they purchased legitimate copies and to request full lifetime licenses, as the Amnesty system doesn’t currently check for proof. However, Klecyznski suggested that the company may start checking some of these claims manually.