diff --git a/src/racket/src/places.c b/src/racket/src/places.c
index f03b9d6c7c..1a5dd4c5e7 100644
--- a/src/racket/src/places.c
+++ b/src/racket/src/places.c
@@ -968,6 +968,7 @@ Scheme_Object *scheme_places_deep_copy_worker(Scheme_Object *so, Scheme_Hash_Tab
         if (copy) {
           SCHEME_CAR(pair) = car;
           SCHEME_CDR(pair) = cdr;          
+          SCHEME_PAIR_COPY_FLAGS(pair, so);
           new_so = pair;
         }
       }
diff --git a/src/racket/src/schpriv.h b/src/racket/src/schpriv.h
index 5e015e5c4d..2ce021113c 100644
--- a/src/racket/src/schpriv.h
+++ b/src/racket/src/schpriv.h
@@ -165,6 +165,9 @@ void scheme_clear_ephemerons(void);
 #define PAIR_IS_NON_LIST 0x2
 #define PAIR_FLAG_MASK 0x3
 
+#define SCHEME_PAIR_COPY_FLAGS(dest, src) (SCHEME_PAIR_FLAGS((dest)) |= (SCHEME_PAIR_FLAGS((src)) & PAIR_FLAG_MASK))
+      
+
 /*========================================================================*/
 /*                             initialization                             */
 /*========================================================================*/