I bought a "Pro" license in 2013. Since then, I have had up to three machines protected using the same license key. Machines came and went, but I was always able to activate my license on a new machine as long as I did not exceed 3. I could do despite the fact that, on my account page, "Managed Devices" showed "0 of 1" available devices.
I recently upgraded a Windows 7 PC to Windows 10. Foolishly, I failed to uninstall Malwarebytes prior to the upgrade. After the upgrade, I went to my account page and"deactivated all" in order to make a fresh start. However after doing so, I unable to register more than a single device!
I contacted Malwarebytes support. They gave me the following explanation:
"Lifetime keys have a Grace Seats Allowed option for up to 3 activations under the condition that customer did not deactivate license key prior to activating again, lost license key due to system crash, etc. However, lifetime keys are good for only one PC after license key reset. You can view the invoice to confirm that the license key is for one device."
I don't have the original EULA, but this explanation is flatly contradicted by my experience. Over the years I have deactivated and reactivated Malwarebytes many times on four or five different machines using the same id and license key (but never more than three at a time) and never had a problem until now.
The terms of the Pro license were guaranteed never to change, but this policy on "grace seats" strikes me as a recent change that was slipped in to trap unwary users.