diff --git a/pyproject.toml b/pyproject.toml
index c072c45b2..d8e281024 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -47,7 +47,7 @@ Issues = "https://github.com/atlanhq/atlan-python/issues"
 
 [dependency-groups]
 dev = [
-    "mypy~=1.9.0",
+    "mypy>=1.9,<1.18",
     "ruff~=0.12.8",
     "types-requests~=2.31.0.6",
     "types-setuptools~=75.8.0.20250110",