diff --git a/pyerrors/input/json.py b/pyerrors/input/json.py
index ca3fb0d2..1273db0f 100644
--- a/pyerrors/input/json.py
+++ b/pyerrors/input/json.py
@@ -59,6 +59,8 @@ def create_json_string(ol, description='', indent=1):
     def _gen_cdata_d_from_list(ol):
         dl = []
         for name in ol[0].cov_names:
+            if _is_uuid4_hex(name):
+                raise ValueError("Cannot safely serialize an Obs derived from a Meas object with a uuid as name. Consider recreating the Meas with an explict name.")
             ed = {}
             ed['id'] = name
             ed['layout'] = str(ol[0].covobs[name].cov.shape).lstrip('(').rstrip(')').rstrip(',')
@@ -216,6 +218,11 @@ def create_json_string(ol, description='', indent=1):
         return json.dumps(d, indent=indent, ensure_ascii=False, default=_jsonifier, write_mode=json.WM_COMPACT)
 
 
+def _is_uuid4_hex(s):
+    uuid4_hex_pattern = re.compile(r'^[0-9a-f]{32}$')
+    return bool(uuid4_hex_pattern.match(s))
+
+
 def dump_to_json(ol, fname, description='', indent=1, gz=True):
     """Export a list of Obs or structures containing Obs to a .json(.gz) file.
     Dict keys that are not JSON-serializable such as floats are converted to strings.
diff --git a/tests/json_io_test.py b/tests/json_io_test.py
index dafaaa41..428704fc 100644
--- a/tests/json_io_test.py
+++ b/tests/json_io_test.py
@@ -409,3 +409,14 @@ def assert_equal_Obs(to, ro):
                 print(kw, "does not match.")
                 return False
     return True
+
+
+def test_meas_uuid(tmp_path):
+    meas = pe.Meas(0.3, 0.2)
+
+    for obs in [meas, meas + 1, meas * pe.pseudo_Obs(0.1, 0.001, "obs|r1")]:
+        with pytest.raises(ValueError):
+            jsonio.dump_to_json([obs], "test_file", indent=1, description='[This file should not be writable]')
+
+    name_meas = pe.Meas(0.3, 0.2, name="my name")
+    jsonio.dump_to_json([name_meas], "test_file", indent=1, description='[This file should be writable]')