Software licenses are are something I *really* don't want to get involved in - I have much better things to do with my time - but I found I was obliged to do so.

It is possible I'm the only person who knows all the following events, as I was the one that instigated them!

The first time I saw ZynAddSubFX source files they were licensed as GPL V2. At that time Zyn had a number of very serious problems, and not much was being done about them. Somewhat naively I asked Lars Luthman if he would help, as he had offered a couple of small patches previously. His response was that he would not do any significant work, as he did not agree with the GPL V2 only license.

I then contacted Paul, explaining the situation and asking if he would consider a change in the license to V2 or later. I was actually a bit surprised that he immediately agreed. When I next looked at the sources, the licenses on the files had indeed been updated, so I passed this information on.

Unfortunately Paul forgot to update the website, but I wasn't especially concerned as it was only the files themselves that really mattered.

While developing Yoshimi after the initial fork, Cal queried the license situation. I told him of the conversations I'd had, and passed him a copy of the email I'd got from Paul. Later on, Cal - in good faith - wrote new sources and placed them under GPL V3. This would be quite compatible with V2 or later, but not with V2 strict.

What I didn't notice until very much later was that Paul had only updated half of the text in the sources, leaving the actual licence in an ambiguous state.

To the best of my knowledge, V3 is not compatible with V2 strict, but V2 or later is. However the *complete* project then becomes downgraded to V2 strict - although the V2 or later sources (such as all the new root/bank code) can independently be freely merged into V3 code.

I doubt anyone would actually make an issue of this. However, to safeguard Yoshimi as a whole, I took it upon myself to change Cal's code to V2 or later. I believe it retains the spirit of his wishes, and the only person with standing to object -  his daughter - has been totally supportive of the work currently being done on Yoshimi.

Any source code I add will be GPL V2 or later.

Update.

The original change discussion has now been located and the license for both Zyn and Yoshi is confirmed as GPL V2 or later.

Anyone wanting to confirm this should look at the Zyn user list archives August 2007 and September 2007.
