Licence & sponsorship
Free and open source.
DDN is available for general public use under the GNU General Public License, version 2 or any later version (GPL-2.0-or-later).
The DDN project
Diagram Design Notation, its viewer, visual designer and verifier, and the DDN website’s own code, documentation and examples are free software. You may use, study, modify and redistribute them under GPLv2 or later. DDN is sponsored by ScratchBird Software Inc., through the Weaver project.
DDN does not require a paid subscription, commercial account or server.
Read or download the GPLv2 licence Copyright and notices Public DDN project
Copyright © ScratchBird Software Inc. and DDN contributors. DDN is supplied without warranty; the full licence states the terms and conditions.
Part of the ScratchBird suite
ScratchBird Software Inc. sponsors DDN as part of its suite of systems software.
- Weaver — the separate commercial platform for collaboration and connected design.
- ScratchBird CDE — the suite’s database system.
- ScratchRobin — the suite’s database client.
DDN’s GPL licence is separate from Weaver’s commercial terms. Weaver’s commercial services are optional and are not required to use DDN. Each other product retains its own licence.
Fonts, icons and other third-party resources
Bundled resources retain their own licences and attribution. The artwork catalogue records the GPL, MIT and CC0/public-domain notices for its individual packs. The optional font licence collection preserves the SIL Open Font License notices. These notices accompany the resources when redistributed.
Product names and standards references identify their respective projects and notation conventions; they do not imply endorsement or certification.