diff --git a/deny.toml b/deny.toml
index 8d82afe..d010ab4 100644
--- a/deny.toml
+++ b/deny.toml
@@ -14,6 +14,7 @@ allow = [
     "Apache-2.0",
     "Apache-2.0 WITH LLVM-exception",
     "Unicode-3.0",
+    "Zlib",
 ]
 confidence-threshold = 0.8