diff --git a/THIRD_PARTY_LICENSES.md b/THIRD_PARTY_LICENSES.md
index 3d06ae5..b43c35f 100644
--- a/THIRD_PARTY_LICENSES.md
+++ b/THIRD_PARTY_LICENSES.md
@@ -24,6 +24,12 @@ Redistributed files:
 The upstream package ships no `NOTICE` file, so the attribution requirement of
 Apache-2.0 section 4(d) does not apply.
 
+### CMaps inside `vendor/cmaps/`
+
+The character maps are Adobe's, not Mozilla's, and carry their own BSD-3-Clause
+terms: © 1990–2009 Adobe Systems Incorporated. The text ships with them in
+`vendor/cmaps/LICENSE` and must stay in place.
+
 ### Fonts inside `vendor/standard_fonts/`
 
 The replacement fonts are not covered by Apache-2.0 and carry their own terms.