diff --git a/hgext/sqlitestore.py b/hgext/sqlitestore.py
--- a/hgext/sqlitestore.py
+++ b/hgext/sqlitestore.py
@@ -615,7 +615,12 @@
         self._revisioncache[node] = revisiondata
         return node
 
-    def addgroup(self, deltas, linkmapper, transaction, addrevisioncb=None):
+    def addgroup(self, deltas, linkmapper, transaction, addrevisioncb=None,
+                 maybemissingparents=False):
+        if maybemissingparents:
+            raise error.Abort(_('SQLite storage does not support missing '
+                                'parents write mode'))
+
         nodes = []
 
         for node, p1, p2, linknode, deltabase, delta, wireflags in deltas:
diff --git a/mercurial/filelog.py b/mercurial/filelog.py
--- a/mercurial/filelog.py
+++ b/mercurial/filelog.py
@@ -7,6 +7,7 @@
 
 from __future__ import absolute_import
 
+from .i18n import _
 from .node import (
     nullid,
     nullrev,
@@ -104,9 +105,14 @@
                                     p1, p2, node=node, flags=flags,
                                     cachedelta=cachedelta)
 
-    def addgroup(self, deltas, linkmapper, transaction, addrevisioncb=None):
+    def addgroup(self, deltas, linkmapper, transaction, addrevisioncb=None,
+                 maybemissingparents=False):
+        if maybemissingparents:
+            raise error.Abort(_('revlog storage does not support missing '
+                                'parents write mode'))
+
         return self._revlog.addgroup(deltas, linkmapper, transaction,
-                                 addrevisioncb=addrevisioncb)
+                                     addrevisioncb=addrevisioncb)
 
     def getstrippoint(self, minlink):
         return self._revlog.getstrippoint(minlink)
diff --git a/mercurial/repository.py b/mercurial/repository.py
--- a/mercurial/repository.py
+++ b/mercurial/repository.py
@@ -693,7 +693,8 @@
         applying raw data from a peer repo.
         """
 
-    def addgroup(deltas, linkmapper, transaction, addrevisioncb=None):
+    def addgroup(deltas, linkmapper, transaction, addrevisioncb=None,
+                 maybemissingparents=False):
         """Process a series of deltas for storage.
 
         ``deltas`` is an iterable of 7-tuples of
@@ -707,6 +708,11 @@
 
         ``addrevisioncb`` should be called for each node as it is committed.
 
+        ``maybemissingparents`` is a bool indicating whether the incoming
+        data may reference parents/ancestor revisions that aren't present.
+        This flag is set when receiving data into a "shallow" store that
+        doesn't hold all history.
+
         Returns a list of nodes that were processed. A node will be in the list
         even if it existed in the store previously.
         """
diff --git a/tests/simplestorerepo.py b/tests/simplestorerepo.py
--- a/tests/simplestorerepo.py
+++ b/tests/simplestorerepo.py
@@ -459,7 +459,12 @@
         self._refreshindex()
         self._svfs.write(self._indexpath, cbor.dumps(self._indexdata))
 
-    def addgroup(self, deltas, linkmapper, transaction, addrevisioncb=None):
+    def addgroup(self, deltas, linkmapper, transaction, addrevisioncb=None,
+                 maybemissingparents=False):
+        if maybemissingparents:
+            raise error.Abort(_('simple store does not support missing parents '
+                                'write mode'))
+
         nodes = []
 
         transaction.addbackup(self._indexpath)