Copyright - SPDX #

SPDX is used to declare metadata about a file, like what license its published under or who owns the copyright. The annotations are usually placed within inline comments at the start of the file.

In cases where the first line of a file is already occupied by for example a shebang declaration #!/usr/bin/env bash, simply place the SPDX annotations on the next lines after.

License #

To declare what license a file falls under, specify the appropriate License Id in the following format:

SPDX-License-Identifier: ‹License Id›

C++ #

// SPDX-License-Identifier: ‹License Id›

Python #

# SPDX-License-Identifier: ‹License Id›

Copyright #

To declare who own the copyright to a file, declare one annotation for every person / organization.

SPDX-FileCopyrightText: ‹Year› ‹Entity›

‹Year› is the year the code was published in.

‹Entity› is either a person or an organization.

Person #

SPDX-FileCopyrightText: 1999 Robert Robertson

Organization #

SPDX-FileCopyrightText: 2000 Crazy CAD Technologies

Examples #

1. Internal C++ Source File #

You just wrote a new .cpp file from scratch and want to license it under the standard license FreeCAD uses ( LGPL-2.1-or-later )

// SPDX-License-Identifier: LGPL-2.1-or-later
// SPDX-FileCopyrightText: 2026 Mike Mc Mickers
// SPDX-FileNotice: Part of the FreeCAD project.

...

2. External C++ Source File #

You want to include some pre-existing code licensed under a compatible but different license to what FreeCAD uses by default.

// SPDX-License-Identifier: MIT
// SPDX-FileCopyrightText: 1939 The Wizard of Oz
// SPDX-FileNotice: Part of the FreeCAD project.

...

3. Mixed Python Licensing #

You have some existing code licensed under one license but also want to add some code under a different license.

# SPDX-License-Identifier: LGPL-2.1-or-later AND MIT
# SPDX-FileCopyrightText: 2010 Technology Inc
# SPDX-FileCopyrightText: 2026 Jane Jay Jensen
# SPDX-FileNotice: Part of the FreeCAD project.

...

4. Executable Python Script #

You have a Python script with a Shebang declaration.

#!/usr/bin/env python3
# SPDX-License-Identifier: LGPL-2.1-or-later
# SPDX-FileCopyrightText: 2011 Nyan Cat
# SPDX-FileNotice: Part of the FreeCAD project.

...

5. Icons #

Icons should have whatever license the author intended, for example CC-BY-SA-4.0.

In svg files this is declared via metadata, not as a SPDX comment.

6. Documentation #

Besides the wiki, currently we don’t license documentation, however you might want to consider putting it under the Unlicense or CC-BY-SA-4.0.