diff --git a/doc/source/groupby.rst b/doc/source/groupby.rst
index cf8ba84ecd4f8..fecc336049a40 100644
--- a/doc/source/groupby.rst
+++ b/doc/source/groupby.rst
@@ -103,8 +103,6 @@ consider the following ``DataFrame``:
 
 .. note::
 
-   .. versionadded:: 0.20
-
    A string passed to ``groupby`` may refer to either a column or an index level.
    If a string matches both a column name and an index level name, a
    ``ValueError`` will be raised.