We don't run the check for a filename passed in as markup if the

  'filename' contains a less-than character; the less-than character
  indicates it's most likely a very small document. [bug=1577864]

2 files changed, 5 insertions, 1 deletions

diff --git a/NEWS.txt b/NEWS.txt
index d81e3f2..76dedd6 100644
--- a/NEWS.txt
+++ b/NEWS.txt
@@ -13,6 +13,10 @@
   were markup. Thanks to James Salter for a patch and
   test. [bug=1533762]
 
+* We don't run the check for a filename passed in as markup if the
+  'filename' contains a less-than character; the less-than character
+  indicates it's most likely a very small document. [bug=1577864]
+
 = 4.4.1 (20150928) =
 
 * Fixed a bug that deranged the tree when part of it was
diff --git a/bs4/__init__.py b/bs4/__init__.py
index da9196d..4df3280 100644
--- a/bs4/__init__.py
+++ b/bs4/__init__.py
@@ -184,7 +184,7 @@ class BeautifulSoup(Tag):
 
         if hasattr(markup, 'read'):        # It's a file-type object.
             markup = markup.read()
-        elif len(markup) <= 256:
+        elif len(markup) <= 256 and not '<' in markup:
             # Print out warnings for a couple beginner problems
             # involving passing non-markup to Beautiful Soup.
             # Beautiful Soup will still parse the input as markup,