diff --git a/Lib/decimal.py b/Lib/decimal.py
index 7c90f0a..4108fb8 100644
--- a/Lib/decimal.py
+++ b/Lib/decimal.py
@@ -5447,7 +5447,7 @@
     # if format type is 'g' or 'G' then a precision of 0 makes little
     # sense; convert it to 1.  Same if format type is unspecified.
     if format_dict['precision'] == 0:
-        if format_dict['type'] in 'gG' or format_dict['type'] is None:
+        if format_dict['type'] is None or format_dict['type'] in 'gG':
             format_dict['precision'] = 1
 
     # record whether return type should be str or unicode
diff --git a/Lib/test/test_decimal.py b/Lib/test/test_decimal.py
index e82a9b9..79b6a85 100644
--- a/Lib/test/test_decimal.py
+++ b/Lib/test/test_decimal.py
@@ -716,6 +716,9 @@
             ('>6', '123', '   123'),
             ('^6', '123', ' 123  '),
             ('=+6', '123', '+  123'),
+
+            # issue 6850
+            ('a=-7.0', '0.12345', 'aaaa0.1'),
             ]
         for fmt, d, result in test_values:
             self.assertEqual(format(Decimal(d), fmt), result)
diff --git a/Misc/NEWS b/Misc/NEWS
index 3522fc8..3162b5a 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -74,6 +74,9 @@
 Library
 -------
 
+- Issue #6850: Fix bug in Decimal._parse_format_specifier for formats
+  with no type specifier.
+
 - Issue #4937: plat-mac/bundlebuilder revers to non-existing version.plist
 
 - Issue #6838: Use a list to accumulate the value instead of