PyCon 2016 in Portland, Or
hills next to breadcrumb illustration

Tuesday 12:10 p.m.–12:55 p.m.

What You Need to Know About Open Source Licenses

Felix Crux

Audience level:


Anyone who uses Open Source has run into software licenses. Too often, our understanding of this mess of legalese is incomplete, confused, or based on bad assumptions. But we can’t ignore them: licenses govern everything about how we use others’ code — and how they use ours. Come learn the basics of copyright, what different licenses let you do, and why & how you should choose one for your code!


Free/Open Source software is everywhere, and software licensing is what enables it. Even though many of us use or develop such software, we often skim over the legalese and hope for the best. But these licenses are vitally important tools in ensuring that others can (or can’t!) benefit from our work in the ways we intended, and the nature of the copyright system is such that ignoring it or making no choice of license means nobody can use your code at all. This talk will cover just what you need to know about intellectual property law, how it relates to software, and why licenses are so important. We’ll examine a number of popular licenses, and in what ways they differ — and how you can use them to achieve different goals. We’ll discuss the difference between permissive and copyleft licenses, and how the copyleft/Free Software movement is using the copyright system against itself to promote their social aims. Promoting any specific license or type of license is explicitly not an objective of the talk, but popular choices within each category will be highlighted. You should come away from this talk with a better understanding of intellectual property law; why it’s important to care about software licenses; what different licenses require from you; how copyleft-style licenses differ from permissive ones; and how to go about choosing a license for your own work. Plus, you’ll hear about the corporate lawyers who had to ask for a special software license allowing them to do evil!