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I could not differentiate between FreeBSD and GPL liecense. Can anyone tell me the in what respect these two liecense are different.

Is it legal to use some source based on GPL license and release the new product as FreeBSD license?

In particular, I have following scence:

I would like to follow some of the implementation module of some implentation for my use. The implementation is standard algorithm implementation. So basically i am taking some reference to implement in my own way. I am not making use of verbatim copy, some module matches with the original one. The one which i am taking reference is in FreeGPL V3 license. The new product which i will release with FreeBSD license. Is it legal to do this or I should relase my product in FreeGPL license?


Moreover, my case is, I am implementing some standard algorithm. Lets say here a data structure linked list. I think,whoever implements it, he/she will have same structure and similar kind of functions for search, delete and insert.Even the operations will be seen. I saw some code in internet and i got the influence of that of code my implementation which was so unavoidable. In this case how can a programmer can claim that the particular code is his own original code?

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You will need legal consultation, but what you're doing sounds like a 'derived work' under GPL terms, because you are, in essence, writing code that is based on GPL'ed code, even if that code is a completely rewrite of the GPL version. Also, I believe that while GPL3 is compatible with FreeBSD-licensed code (as in, you can include FreeBSD-licensed software under your GPL3 software), the opposite is not true (you can not include GPL3 code in your FreeBSD licensed software). It's a one way license compatibility. – birryree Feb 23 '12 at 20:24
The particular situation here is really uncertain, as it's hard to tell if a court will find that you are creating a "derivative work" or not. Larger organizations often do this in a "clean room" fashion - one set of people examine the code and write a spec, and another set implements the spec without looking at the outside code. – David Thornley Feb 23 '12 at 22:42
What is the FreeGPL license? Do you mean the usual GPL? – user281377 Feb 23 '12 at 23:59
Exactly , I mean to say GPLv3.Sorry it was typo. – thetna Feb 24 '12 at 0:32

The question isn't "how can a programmer can claim that the particular code is his own original code?', the question is "did you base your code on the GPL'ed code?". If you did, then your stuck with releasing it under the GPL.

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Yes i based on the GPL'ed code. But I am integrating the particular piece of code in a software which has FreeBSD license.I am freeing the code but the only thing is it differs the license. – thetna Feb 23 '12 at 22:53
I have not yet release the code. I would like to make sure if it is legal or not. – thetna Feb 23 '12 at 22:55
It would appear you can't do what you want to do. The Free Software Foundation, which is something of an expert on code licenses says ( that while the BSD license is compatible with the GPL, you must release your derived code under the GPL. Sorry. – Ross Patterson Feb 24 '12 at 12:40
Is it possible for me to release a derived code both in GPL and FreeBSD license at a time? – thetna Feb 24 '12 at 13:51
Let me put it more succinctly: it would appear that you are not allowed to release your code under any license except the GPL. – Ross Patterson Feb 24 '12 at 20:34

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