diff --git a/src/calibre/ebooks/metadata/sources/identify.py b/src/calibre/ebooks/metadata/sources/identify.py
index 97b6d15bc8..a7bcbc5a89 100644
--- a/src/calibre/ebooks/metadata/sources/identify.py
+++ b/src/calibre/ebooks/metadata/sources/identify.py
@@ -22,6 +22,7 @@ from calibre.ebooks.metadata.book.base import Metadata
 from calibre.utils.date import utc_tz, as_utc
 from calibre.utils.html2text import html2text
 from calibre.utils.icu import lower
+from calibre.utils.date import UNDEFINED_DATE
 
 # Download worker {{{
 class Worker(Thread):
@@ -490,6 +491,8 @@ def identify(log, abort, # {{{
     max_tags = msprefs['max_tags']
     for r in results:
         r.tags = r.tags[:max_tags]
+        if getattr(r.pubdate, 'year', 2000) <= UNDEFINED_DATE.year:
+            r.pubdate = None
 
     if msprefs['swap_author_names']:
         for r in results: