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Open Source in Finance Podcast: Understanding Copyleft - Aaron Williamson

August 15, 2021
On this episode of the podcast we talk open source readiness, compliance, and how to understand the copyleft license. Copyleft licenses like the GNU GPL come with a higher compliance burden than more permissive licenses, because they require licensees to provide source code to recipients -- sometimes just for the open source component, and sometimes for any derivative work produced by the licensee. These licenses therefore raise the thorniest issues of license compliance.
Episode show notes are available below.

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In this podcast, FINOS Open Source Readiness lead Aaron Williamson discusses:

  • What is a derivative work of a software project
  • What constitutes distribution under copyright law
  • Incompatibility issues between copyleft and other licenses
  • The differences between GPL versions 2 and 3


Aaron Williamson:

PDF slides to follow along:

Video version:

FINOS Open Source License Compliance Handbook:


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About the Open Source in FINANCE Podcast

The FINOS Open Source in Finance Podcast celebrates open source projects and interesting topics at the cross section of financial services and open source. So far, our industry experts have discussed practical applications of and their real-world experiences with a range of open source projects including desktop interoperability, low code platforms, synthetic data, and data modeling. They’ve also discussed best practices for inner source, common myths about open source and why commercial companies choose to introduce open source offerings. Tune in and subscribe to hear what comes next.

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