CeCILL-CThe library-oriented weak-copyleft branch of the CeCILL family, roughly parallel to LGPL-style use cases.Common Development and Distribution License 1.0File-based weak copyleft license derived from MPL 1.1, used by projects such as OpenZFS and Illumos descendants.Common Development and Distribution License 1.1Updated CDDL revision retaining the same general file-level weak-copyleft structure.Eclipse Public License 1.0The earlier Eclipse weak-copyleft license, historically important in Java tooling and enterprise software.Eclipse Public License 2.0Weak copyleft used across the Eclipse ecosystem, designed around modularity and commercial compatibility.European Union Public License 1.2European public-sector weak copyleft license with explicit compatibility language for multiple other licenses.GNU Lesser General Public License v2.1The classic weak-copyleft library license of the pre-v3 GNU era, still common across infrastructure software.GNU Lesser General Public License v3.0Weak copyleft for libraries: the library itself stays free, but proprietary programs may link against it.GNU Lesser General Public License v3.0 onlyLGPLv3 without the “or later” clause, preserving the exact GNU weak-copyleft text of version 3 only.GNU Library General Public License v2.0The older “Library GPL” predecessor to LGPL 2.1, historically significant in early free software libraries.Mozilla Public License 1.1The older Mozilla file-level weak copyleft, historically important before the simplification and compatibility work of MPL 2.0.Mozilla Public License 2.0File-level copyleft used by Firefox and Thunderbird — a middle ground between GPL and permissive licenses.