Yes
Most weak-copyleft licenses (including GNU Lesser GPL v2.1) are designed to combine with GPL-family ones. Verify the specific weak-copyleft license version against GNU General Public License v2.0's compatibility list (FSF maintains an authoritative one).
| License | Family | Patent grant |
|---|---|---|
| GNU Lesser GPL v2.1 (LGPL-2.1) | weak-copyleft | No (implicit at most) |
| GNU General Public License v2.0 (GPL-2.0) | strong-copyleft | No (implicit at most) |
GNU Lesser GPL v2.1: Library copyleft: dynamic linking permitted from non-LGPL code without triggering full copyleft.
GNU General Public License v2.0: Strong copyleft: derivative works distributed must also be GPL-2.0.
If you found this page because you're trying to figure out whether shipping a particular dependency is safe, the answer above is a starting point — not a substitute for reading the actual licenses or talking to a lawyer when stakes are high.
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