Open Source Licensing: An Overview

Transcription

1 Open Source Licensing: An Overview Alexander Champoux Trinity College April 28, 2008

2 Introduction My paper for HFOSS is on Open Source Licensing Without some of the flexibilities and constraints of Open Source Licenses the FOSS movement couldn't function. My goal in this presentation is to provide a clear guide to understanding the available licenses and how they are made/used. Are you ready?

3 What Is Open Source Licensing A new breed of licensing that provides for the Open Source community. Must meet certain standards to be considered Open Source The Open Source Initiative and Free Software Foundation are the two main organizations in charge of OSL accreditation. Open Source Licenses tend to be graded off of the Open Source Definition presented by Stallman.

4 Accreditation Process OSI Licenses categorized Put to the community for review Community voices opinion OSI License Review Chair presents recommendations to the OSI Board OSI Board accepts/denies If accepted the license is categorized and listed on the OSI website

5 History of Open Source Licensing Free Software Foundation founded by Stallman in 1985 Open Source Initiative founded in 1998 by Eric Raymond and Bruce Perens First open source licenses BSD licenses 1982 Gnu GPL first cohesive and multi purpose license in 1983

6 Sun Microsystems OSL Ratings Class A: No requirement on derivative works to use the same license. Unrestricted scope of license use (you can use any part and relicense under another license, even a closed one.). BSD, Apache, MIT, Eclipse Class B: Copyleft licenses that require that the derivative work use the same license as before. Can be licensed under a different license (even closed source) if the work is not derivative and only uses source samples. Common Development and Distribution License, Mozilla Public License Class C: Strong copyleft licenses that require derivative (and most non derivative) works to use the same license. Gnu GPL, Gnu LGPL, CPL

7 Most Used Licenses and Their Uses Gnu GPL: Requires user to license under GPL again. Guarantees open source. BSD: Allows user to take and relicense under closed licenses. Apache: Also allows relicensing under a new (and potentially closed) license, but also places a few more restrictions on the user than BSD. MIT License: Similar to BSD in permissiveness. Mozilla Public License: More copyleft than permissive, it still falls short of the GPL by allowing some incorporation into proprietary works without considering that work a derivative. Common Public License: Even more strict than the GPL, also slightly ambiguous in some sectors. Sort of like GPL, but allows new licenses to exist. Common Public License: Eclipse Public License: Sort of like GPL, but allows new licenses to exist. Gnu 'Lesser' GPL: A little more permissive than GPL, but still strong copyleft. Encourages sharing more than GPL. Common Development & Distribution License: More permissive than GPL, allows relicensing.

8 Pros, Cons, Legal Strength Pros: In all cases, these licenses promote the sharing of knowledge and provide for the distribution of code. In the case of copyleft licenses they ensure viral proliferation of the open source movement. Open source licenses also provide for commercial sale of licensed property as well, which protects our right to make major coin!!! Cons: Cannot, in most cases, be mixed with proprietary software as there is a conflict of interest meaning you'll have to infringe either the open or closed license in distribution. Pros: Cons: Legal Strength: Just as strong as any copyright, holders of open source licenses have never lost in court. In fact, in the case of the SCO vs. IBM lawsuit, it turned the case on its head. Say the lawyers: don't mess with open source licenses. Even cooler: Open Source Licenses are virtually immortal because they renew every time you modify code. So, yeah, in 100 years anyone can use the original code, but by that point it will be completely obsolete.

9 Selected References Free and Open Source Licensing White Paper, 2006 Sun Microsystems, Inc., pages source licensing Interview with Peter Guffin, Partner Pierce Atwood and specialist in Intellectual Property Law and Licensing