diff --git a/src/sdf/ftsdfrend.c b/src/sdf/ftsdfrend.c
index 420ad496c..6fd104dbf 100644
--- a/src/sdf/ftsdfrend.c
+++ b/src/sdf/ftsdfrend.c
@@ -350,6 +350,8 @@
     error = render->raster_render( render->raster,
                                    (const FT_Raster_Params*)&params );
 
+    if ( x_shift || y_shift )
+      FT_Outline_Translate( outline, -x_shift, -y_shift );
   Exit:
     if ( !error )
     {
@@ -362,9 +364,6 @@
       slot->internal->flags &= ~FT_GLYPH_OWN_BITMAP;
     }
 
-    if ( x_shift || y_shift )
-      FT_Outline_Translate( outline, -x_shift, -y_shift );
-
     return error;
   }
 
@@ -506,6 +505,16 @@
       goto Exit;
     }
 
+    /* do not convert to SDF if the bitmap is not owned by glyph */
+    if ( !(slot->internal->flags & FT_GLYPH_OWN_BITMAP) )
+    {
+      FT_ERROR(( "ft_bsdf_render: can't convert bitmap to sdf;\n" ));
+      FT_ERROR(( "                bitmap not owned by glyph.\n"   ));
+
+      error = FT_THROW( Invalid_Argument );
+      goto Exit;
+    }
+
     if ( !bitmap->rows || !bitmap->pitch )
       goto Exit;