diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4a77abf56..9577d866d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -20,6 +20,7 @@
 - pin `weldx-widgets>=0.2.3` for viz \[{pull}`939`\].
 - pin `pint>=0.21` \[{pull}`941`\].
 - pin `python<3.13` \[{pull}`896`\].
+- pin `asdf<4` \[{pull}`952`\].
 
 ## 0.6.8 (07.06.2024)
 
diff --git a/pyproject.toml b/pyproject.toml
index 1e61ed9b6..bb4dff8a3 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -42,7 +42,7 @@ dynamic = [
   "version", # version gets derived from git by setuptools_scm.
 ]
 dependencies = [
-  "asdf>=2.15.1",
+  "asdf>=2.15.1,<4",
   "bidict",
   "boltons",
   "bottleneck>=1.3.3",