diff --git a/src/calibre/ebooks/metadata/__init__.py b/src/calibre/ebooks/metadata/__init__.py
index 02401b25e6..847d69597c 100644
--- a/src/calibre/ebooks/metadata/__init__.py
+++ b/src/calibre/ebooks/metadata/__init__.py
@@ -36,9 +36,10 @@ def author_to_author_sort(author):
         return author
     author = _bracket_pat.sub('', author).strip()
     tokens = author.split()
-    tokens = tokens[-1:] + tokens[:-1]
-    if len(tokens) > 1 and method != 'nocomma':
-        tokens[0] += ','
+    if tokens[-1] not in ('Inc.', 'Inc'):
+        tokens = tokens[-1:] + tokens[:-1]
+        if len(tokens) > 1 and method != 'nocomma':
+            tokens[0] += ','
     return ' '.join(tokens)
 
 def authors_to_sort_string(authors):