diff --git a/bisect/42505.py b/bisect/42505.py
new file mode 100644
index 0000000000000..6f4cf9ee01782
--- /dev/null
+++ b/bisect/42505.py
@@ -0,0 +1,11 @@
+# BUG: Regression - AmbiguousTimeError creating DataFrame #42505
+
+import pandas as pd
+
+print(pd.__version__)
+
+dt = pd.to_datetime("2019-11-03 01:00:00-0700").tz_convert("America/Los_Angeles")
+
+result = pd.DataFrame({"dt": dt, "value": [1]})
+print(result)
+print(result.dtypes)