diff --git a/src/calibre/devices/usbms/books.py b/src/calibre/devices/usbms/books.py
index 4d5110b049..3e13527bd0 100644
--- a/src/calibre/devices/usbms/books.py
+++ b/src/calibre/devices/usbms/books.py
@@ -59,7 +59,7 @@ class Book(Metadata):
         return property(doc=doc, fget=fget)
 
     @dynamic_property
-    def thumbnail(self):'
+    def thumbnail(self):
         return None
 
 class BookList(_BookList):
diff --git a/src/calibre/ebooks/metadata/book/__init__.py b/src/calibre/ebooks/metadata/book/__init__.py
index 84a88606f2..e7f58ce858 100644
--- a/src/calibre/ebooks/metadata/book/__init__.py
+++ b/src/calibre/ebooks/metadata/book/__init__.py
@@ -110,7 +110,7 @@ COPYABLE_METADATA_FIELDS = SOCIAL_METADATA_FIELDS.union(
                            frozenset(['title', 'title_sort', 'authors',
                                       'author_sort', 'author_sort_map' 'comments',
                                       'cover_data', 'tags', 'language', 'lpath',
-                                      'size', 'thumbnail'])
+                                      'size'])
 
 SERIALIZABLE_FIELDS =      SOCIAL_METADATA_FIELDS.union(
                            USER_METADATA_FIELDS).union(