diff --git a/CHANGES b/CHANGES
index 29d22dd..26944b8 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,6 +1,7 @@
 0.9.5 UNRELEASED
  - Beta 1 (updated Alpha -> Beta warning in README and trove classifiers)
- - Add support for MacroList option
+ - Added support for MacroList option
+ - Added support for MacroListVerify option
 
 0.9.4 2018-03-09
  - Create PID directory if it is missing
diff --git a/dkimpy_milter/__init__.py b/dkimpy_milter/__init__.py
index 02221ca..2296cb9 100644
--- a/dkimpy_milter/__init__.py
+++ b/dkimpy_milter/__init__.py
@@ -60,6 +60,7 @@ class dkimMilter(Milter.Base):
   @Milter.noreply
   def connect(self,hostname,unused,hostaddr):
     self.internal_connection = False
+    self.external_connection = False
     self.hello_name = None
     # sometimes people put extra space in sendmail config, so we strip
     self.receiver = self.getsymval('j').strip()
@@ -83,6 +84,15 @@ class dkimMilter(Milter.Base):
             if (len(macro.split('|')) == 1 and macroresult) or macroresult in \
                     macro.split('|')[1:]:
                 self.internal_connection = True
+    if milterconfig.get('MacroListVerify'):
+        macrolist = milterconfig.get('MacroListVerify')
+        for macro in macrolist:
+            macroname = macro.split('|')[0]
+            macroname = '{' + macroname + '}'
+            macroresult = self.getsymval(macroname)
+            if (len(macro.split('|')) == 1 and macroresult) or macroresult in \
+                    macro.split('|')[1:]:
+                self.external_connection = True
     if self.internal_connection:
         connecttype = 'INTERNAL'
     else:
@@ -163,7 +173,7 @@ class dkimMilter(Milter.Base):
         domain = milterconfig.get('Domain')
     else:
         domain = ''
-    if (self.fdomain in domain) and (not milterconfig.get('Mode') == 'v'):
+    if (self.fdomain in domain) and ((not milterconfig.get('Mode') == 'v') or not self.external_connection):
       txt = self.fp.read()
       self.sign_dkim(txt)
       result = None
diff --git a/dkimpy_milter/config.py b/dkimpy_milter/config.py
index 1b3a6b2..7c7fc58 100644
--- a/dkimpy_milter/config.py
+++ b/dkimpy_milter/config.py
@@ -48,7 +48,8 @@ defaultConfigData = {
         'InternalHosts' : '127.0.0.1',
         'InternalHostsObj' : False,
         'DiagnosticDirectory' : '',
-        'MacroList' : ''
+        'MacroList' : '',
+        'MacroListVerify' : ''
         }
 
 
@@ -337,7 +338,8 @@ def _readConfigFile(path, configData = None, configGlobal = {}):
         'InternalHosts' : 'dataset',
         'InternalHostsObj': 'bool',
         'DiagnosticDirectory' : 'str',
-        'MacroList' : 'dataset'
+        'MacroList' : 'dataset',
+        'MacroListVerify' : 'dataset'
             }
 
     #  check to see if it's a file
diff --git a/man/dkimpy-milter.conf.5 b/man/dkimpy-milter.conf.5
index 4d9b36f..a6f8b5e 100644
--- a/man/dkimpy-milter.conf.5
+++ b/man/dkimpy-milter.conf.5
@@ -289,6 +289,16 @@ at the time the filter receives a connection from the MTA and its availability
 depends upon the version of milter used to compile the filter and the version
 of the MTA making the connection.
 
+.TP
+.I MacroListVerify (dataset)
+Defines a set of MTA-provided
+.I macros
+that should be checked to see if the sender has been determined to be an
+external source and therefore whether or not the message should be signed.
+Entries in this data set follow the same form as those of the
+.I MacroList
+option above.  [this option is not inhereted from OpenDKIM]  
+
 .TP
 .I Mode (string)
 Selects operating modes.  The string is a concatenation of characters that