We want to use Automapper in commercial application (.NET 3.5). To get the clearance we need the source code of automapper.
We got the required automapper source code but after building the code we found that the size of automapper.dll 86KB while the DLL we were using was of 108 KB. Application was not working with this 86KB automapper dll
We looked into the code and found that another DLL LinFu.DynamicProxy of size 21KB . If I use this DLL with automapper DLL application works fine.
Based on that I conclude that the 108KB dll that I was using actually contains 86KB Automapper + 21 KB LinFu.DynamicProxy.
Now I have question related to licensing. Do I need to get the approval for LinFu.DynamicProxy as well. It comes with GNU license.
Linfu appears to be licensed under L GPL (Lesser GPL).
The "Lesser" basically means you can use it in your application as an external component without having to change the license of your project (this isn't the exact definition of the license, you'll have to read it for the precise terms, but it's the general idea). The LGPL license is often used for open source libraries because you can easily embed them in commercial projects without impact to the commercial product itself.
If you do not plan to modify the Linfu dll, you can ship it with your commercial product. You don't even need to ask the permission to their author (if they licensed their project under LGPL, you already have the authorization). Just make sure you ship a readme.txt file (for example) that says Linfu is under LGPL plus a link to the LGPL, it should be OK.