diff --git a/bec_ipython_client/pyproject.toml b/bec_ipython_client/pyproject.toml
index 8a89b2b7c..fd23d7ff7 100644
--- a/bec_ipython_client/pyproject.toml
+++ b/bec_ipython_client/pyproject.toml
@@ -25,7 +25,7 @@ dependencies = [
 dev = [
     "black~=26.0",
     "coverage~=7.0",
-    "isort~=5.13, >=5.13.2",
+    "isort>=5.13, <9.0",
     "pylint~=3.0",
     "pytest-bec-e2e~=3.0",
     "pytest-random-order~=1.1",
diff --git a/bec_lib/pyproject.toml b/bec_lib/pyproject.toml
index 9db618301..de9192f0c 100644
--- a/bec_lib/pyproject.toml
+++ b/bec_lib/pyproject.toml
@@ -46,7 +46,7 @@ dev = [
     "black~=26.0",
     "coverage~=7.0",
     "fakeredis~=2.23, >=2.23.2",
-    "isort~=5.13, >=5.13.2",
+    "isort>=5.13, <9.0",
     "pandas~=2.0",
     "pytest>=8,<10",
     "pytest-random-order~=1.1",
diff --git a/bec_server/pyproject.toml b/bec_server/pyproject.toml
index 7838f3ac3..1edfd16b0 100644
--- a/bec_server/pyproject.toml
+++ b/bec_server/pyproject.toml
@@ -34,7 +34,7 @@ dev = [
     "black~=26.0",
     "coverage~=7.0",
     "fakeredis~=2.23, >=2.23.2",
-    "isort~=5.13, >=5.13.2",
+    "isort>=5.13, <9.0",
     "pylint~=3.0",
     "pytest>=8,<10",
     "pytest-random-order~=1.1",