diff --git a/hgext3rd/uncommit.py b/hgext3rd/uncommit.py
--- a/hgext3rd/uncommit.py
+++ b/hgext3rd/uncommit.py
@@ -44,8 +44,9 @@
         repo._bookmarks.applychanges(repo, tr, changes)
 
 def _commitfiltered(repo, ctx, match):
-    """Recommit ctx with changed files not in match. Return the new
-    node identifier, or None if nothing changed.
+    """Recommit ctx with changed files not in match. Returns tuple of
+    (newid, isnew), where newid is the new node identifier, or None if
+    nothing changed, and isnew is True if the new node is a new commit.
     """
     base = ctx.p1()
     # ctx
@@ -54,11 +55,11 @@
 
     # No files matched commit, so nothing excluded
     if not exclude:
-        return None
+        return None, False
 
     files = (initialfiles - exclude)
     if not files:
-        return ctx.parents()[0].node()
+        return ctx.parents()[0].node(), False
 
     # Filter copies
     copied = copies.pathcopies(base, ctx)
@@ -83,7 +84,7 @@
                          date=ctx.date(),
                          extra=ctx.extra())
     newid = repo.commitctx(new)
-    return newid
+    return newid, True
 
 def _uncommitdirstate(repo, oldctx, match):
     """Fix the dirstate after switching the working directory from
@@ -157,13 +158,16 @@
 
         with repo.transaction('uncommit') as tr:
             match = scmutil.match(old, pats, opts)
-            newid = _commitfiltered(repo, old, match)
+            newid, isnew = _commitfiltered(repo, old, match)
             if newid is None:
                 raise error.Abort(_('nothing to uncommit'))
 
             # Move local changes on filtered changeset
-            obsolete.createmarkers(repo, [(old, (repo[newid],))])
-            phases.retractboundary(repo, tr, oldphase, [newid])
+            if isnew:
+                obsolete.createmarkers(repo, [(old, (repo[newid],))])
+                phases.retractboundary(repo, tr, oldphase, [newid])
+            else:
+                obsolete.createmarkers(repo, [(old, ())])
 
             with repo.dirstate.parentchange():
                 repo.dirstate.setparents(newid, node.nullid)
diff --git a/tests/test-uncommit.t b/tests/test-uncommit.t
--- a/tests/test-uncommit.t
+++ b/tests/test-uncommit.t
@@ -174,4 +174,29 @@
   |/
   o  0:3004d2d9b50883c1538fc754a3aeb55f1b4084f6 added file-a
   
+Uncommit with draft parent
 
+  $ hg uncommit
+  $ hg phase -r .
+  10: draft
+  $ hg commit -m 'update ab again'
+
+Uncommit with public parent
+
+  $ hg phase -p "::.^"
+  $ hg uncommit
+  $ hg phase -r .
+  10: public
+
+Partial uncommit with public parent
+
+  $ echo xyz > xyz
+  $ hg add xyz
+  $ hg commit -m "update ab and add xyz"
+  $ hg uncommit xyz
+  $ hg status
+  A xyz
+  $ hg phase -r .
+  14: draft
+  $ hg phase -r ".^"
+  10: public