Previously I posted about an instance of copyright infringement. It was found that a company called HamsterSoft was using portions of calibre in their proprietary and closed source ebook conversion program. The good news is the situation has been resolved.

On August 15th I was contacted by Pavel, one of the founders of HamsterSoft. He said that they are committed to their Hamster Free eBook Converter (HFEC) program and they feel compliance with calibre’s license (the GNU GPL v3) is their only option. He also informed me that they had stopped distribution of HFEC. Pavel ask if I could give them a few weeks to prepare the source code for release. He also wanted me to know that their support email address was posted in error and it is not checked.

I took the fact that they had stopped distribution and wanted to comply with the GPL as a sign of good faith. I told him that we’re happy to see people using calibre in new and interesting ways as long as it’s in compliance with the GPL. I also told him that as long as they’ve stopped distribution they can take as much time as they need to prepare the source code for release.

On August 17th I received another email from Pavel. He said that they are not experienced with the GPL and would like for me to look at the source package they have prepared. He also asked for me to confirm that it would comply with the GPL and they would not restart distribution until I approved the package or a subsequent version if this one was not in compliance.

I looked at the package and replied that as long as all source is included that it is in compliance. From looking though the package it appeared that everything was included. The binary component that was missing from the first package was included in source form in this one. I also suggested that that a license.txt file with information about the code licensing be included so there is no confusion.

As of August 18th HamsterSoft posted the following apology letter:



HamsterSoft, on behalf of all its members, would like to apologize to Kovid Goyal and John Schember for the fact that since the launch of the Hamster Free eBook Converter program our company has not satisfied all of the GPL v.3 license conditions.

Our Company developers realize that the creators of Calibre have made enormous efforts during the past few years, and we respect the labor of other programmers. It was distressing for us to discover that we, either directly or indirectly, have impeded the work of others – that we have not supported their idea of development of the new software on the basis of open code.

Over the last few days we have conducted a lot of work in order to eliminate the existing defects. We hope that Kovid, John, and the other Calibre developers will consider the license agreement met and community interests complied with, and that they will accept our sincere apologies so that our company can continue to efficiently and easily create new free software for forty world languages.

Also, as of August 18th they have posted the complete source code for HFEC. At this time they have not yet fully restored their website (it’s only partly) for easily downloading HFEC as an installable Windows program.

I’m willing to accept that any past dealings in regard to this matter are a result of a misunderstanding. I’m also willing to accept from communication with Pavel and HamserSoft’s actions that they genuinely wanted to comply with the GPL. I accept HamsterSoft’s apology and I am reinstating all rights afforded to them under the GPL to my work that is part of calibre. They are now in compliance with the GPL and no longer violating my copyright.