diff --git a/dep_freshness/tests/test_versions.py b/dep_freshness/tests/test_versions.py
index 969e3a8..70f5204 100644
--- a/dep_freshness/tests/test_versions.py
+++ b/dep_freshness/tests/test_versions.py
@@ -34,7 +34,10 @@ def test_newest_stable_ignores_unparseable_entries():
 
 @pytest.mark.parametrize("raw,expected", [
     ("1.6.0", "1.6.0"), ("==1.6.0", "1.6.0"), ("v2.0.0", "2.0.0"),
-    ("  1.0.0  ", "1.0.0"),
+    ("  1.0.0  ", "1.0.0"), ("1.9", "1.9"), ("3", "3"),
+    # PyPI stub packages date-stamp a fourth component. Capping the regex at
+    # three reported this exact pin as unpinned *against its own value*.
+    ("==2.33.0.20260712", "2.33.0.20260712"),
 ])
 def test_exact_pins_are_recognised(raw, expected):
     assert exact_pin(raw) == expected
diff --git a/dep_freshness/versions.py b/dep_freshness/versions.py
index 0a63e2e..1929424 100644
--- a/dep_freshness/versions.py
+++ b/dep_freshness/versions.py
@@ -74,7 +74,10 @@ def behind(pinned: str, latest: str) -> bool:
     return left < right
 
 
-EXACT = re.compile(r"^\s*(?:==\s*)?v?\d+(?:\.\d+){0,2}(?:[-+][0-9A-Za-z.-]+)?\s*$")
+# Any number of numeric release components, not three: PyPI stub packages
+# date-stamp a fourth (`types-requests==2.33.0.20260712`), and capping at
+# three reported an exact pin as unpinned against itself.
+EXACT = re.compile(r"^\s*(?:==\s*)?v?\d+(?:\.\d+)*(?:[-+][0-9A-Za-z.-]+)?\s*$")
 
 
 def exact_pin(constraint: str) -> str | None: