# In defense of extreme copyleft ## Henrik Ingo ### State of the Source 2020 ----- # Agenda * Cryptographic Autonomy License * Server Side Public License * BSD + Patents ----- ## Spectrum Permissive < - > Copyleft BSD/MIT    Apache    Mozilla    LGPL    GPL    AGPL    **This talk** ----- 4.2. Maintain User Autonomy. In addition to providing each Recipient the opportunity to have Access to the Source Code, You cannot use the permissions given under this License to interfere with a Recipient’s ability to fully use an independent copy of the Work generated from the Source Code You provide with the Recipient’s own User Data. ----- “User Data” means any data that is an input to or an output from the Work, where the presence of the data is necessary for substantially identical use of the Work in an equivalent context chosen by the Recipient, and where the Recipient has an existing ownership interest, an existing right to possess, or where the data has been generated by, for, or has been assigned to the Recipient. -----  ----- ### AGPL 13 Remote Network Interaction; Use with the GNU General Public License. Notwithstanding any other provision of this License, **if you modify the Program, your ** **modified version must prominently offer all users interacting with it remotely through a** **computer network (if your version supports such interaction)** an opportunity to receive the Corresponding Source of your version by providing access to the Corresponding Source from a network server at no charge, through some standard or customary means of facilitating copying of software. This Corresponding Source shall include the Corresponding Source for any work covered by version 3 of the GNU General Public License that is incorporated pursuant to the following paragraph. ----- # Apache Software License 3 Grant of Patent License. ... **where ** **such license applies only to those patent claims licensable by such Contributor that ** **are necessarily infringed by** their Contribution(s) alone or by combination of their Contribution(s) with the Work to which such Contribution(s) was submitted. ----- # GPL A contributor's **“essential patent claims”** are all patent claims owned or controlled by the contributor, ... but do not include claims that would be infringed only as a consequence of further modification of the contributor version. . ----- ### Summary 1. CAL extends copyleft to user data * Also fixes some issues with AGPL, such as software without UI. 2. Copyleft for microservice architecture is a valid concept. 3. Copyleft for patents * Not just essential claims! .