Relicensing OCCT

Dear all,

I'm very pleased to inform you that the next version of Open CASCADE Technology (OCCT) - 6.7.0 - will be licensed under the GNU Lesser General Public License (LGPL) version 2.1.

This relicensing will not change the license of already published OCCT versions up to 6.6.0.

Daniel Brunier-Coulin

István Csanády's picture


There is a long thread about LGPL vs Apple AppStore on stackoverflow:

It is not clear that uploading an application to the app store violates LGPL or not, the common practice is that the owner of the libraries can decide whether they allow distribution in the app store or not.
So my question is, that if I provide the static iOS libraries for OCCT, are you going to allow to distribute my application in the AppStore, or not?
I have just signed the CLA, and I am developing an app to iOS, so this is a fundamental issue for me.

Daniel Brunier-Coulin's picture


The license of OCCT up to version 6.6.0 will not change - it's from version 6.7.0 that OCCT will be licensed under LGPL.
The license of OCCT 6.6.0 allowing you to statically link your application with OCCT, you can use this version.


István Csanády's picture

LGPL allows static linking as well in special circumstances, as it is pointed out in the referenced forum thread. As it is shown, it is not clear if the AppStore distribution violates the LGPL or not, in practice, it depends on the author of the library whether they allow it or not. Eg. FFMPEG allows distributing applications in the AppStore, just like many other LGPL library authors.
My intentions are clear: I want to contribute to OCCT, I want to publish my changes (for example the build system for iOS libraries, and compiled libraries), but the AppStore vs. LGPL problem basically depends on you.

It is obviously not acceptable to use an unmaintained library in a production quality code (OCC6.6.0).

Daniel Brunier-Coulin's picture

I understand your point, Itsvan, and be sure, we are considering it, but before answering you less generically, we need to fully understand the issue, both technically and legally, which takes a bit of time, especially when the situation is not completely clear.

thomas paviot's picture

Dear Daniel,

This is a very good news, definitely. The licensing issues wasted a big amount of time for both OCC teams and community. May this decision lead to a more constructive relationship between all of us sharing the same interest.


Jayden Shui's picture

When will OCCT 6.7.0 released? I'm looking forward to it. Thanks.

Daniel Brunier-Coulin's picture

Hopefully before Christmas.