diff --git a/src/aig/gia/gia.h b/src/aig/gia/gia.h
index 015a1da22..31761a735 100644
--- a/src/aig/gia/gia.h
+++ b/src/aig/gia/gia.h
@@ -1436,6 +1436,7 @@ extern void                Gia_ManEquivFixOutputPairs( Gia_Man_t * p );
 extern int                 Gia_ManCheckTopoOrder( Gia_Man_t * p );
 extern int *               Gia_ManDeriveNexts( Gia_Man_t * p );
 extern void                Gia_ManDeriveReprs( Gia_Man_t * p );
+extern void                Gia_ManDeriveReprsFromSibls( Gia_Man_t *p );
 extern int                 Gia_ManEquivCountLits( Gia_Man_t * p );
 extern int                 Gia_ManEquivCountLitsAll( Gia_Man_t * p );
 extern int                 Gia_ManEquivCountClasses( Gia_Man_t * p );
diff --git a/src/aig/gia/giaAig.c b/src/aig/gia/giaAig.c
index c764a0993..07bab5fec 100644
--- a/src/aig/gia/giaAig.c
+++ b/src/aig/gia/giaAig.c
@@ -19,10 +19,12 @@
 ***********************************************************************/
 
 #include "giaAig.h"
+#include "aig/gia/gia.h"
 #include "proof/fra/fra.h"
 #include "proof/dch/dch.h"
 #include "opt/dar/dar.h"
 #include "opt/dau/dau.h"
+#include <assert.h>
 
 ABC_NAMESPACE_IMPL_START
 
@@ -191,6 +193,8 @@ Gia_Man_t * Gia_ManFromAigChoices( Aig_Man_t * p )
     Gia_ManSetRegNum( pNew, Aig_ManRegNum(p) );
     //assert( Gia_ManObjNum(pNew) == Aig_ManObjNum(p) );
     //Gia_ManCheckChoices( pNew );
+    if ( pNew->pSibls )
+        Gia_ManDeriveReprsFromSibls( pNew );
     return pNew;
 }
 
diff --git a/src/aig/gia/giaEquiv.c b/src/aig/gia/giaEquiv.c
index e4f5a0d25..36e604153 100644
--- a/src/aig/gia/giaEquiv.c
+++ b/src/aig/gia/giaEquiv.c
@@ -310,6 +310,39 @@ void Gia_ManDeriveReprs( Gia_Man_t * p )
     }
 }
 
+/**Function*************************************************************
+
+  Synopsis    [Given pSibls, derives original representitives and nexts.]
+
+  Description []
+               
+  SideEffects []
+
+  SeeAlso     []
+
+***********************************************************************/
+
+void Gia_ManDeriveReprsFromSibls( Gia_Man_t *p )
+{
+    
+    int i, iObj;
+    assert( !p->pReprs && p->pSibls );
+    p->pReprs = ABC_CALLOC( Gia_Rpr_t, Gia_ManObjNum(p) );
+    for ( i = 0; i < Gia_ManObjNum(p); i++ )
+        Gia_ObjSetRepr( p, i, GIA_VOID );
+    for ( i = 0; i < Gia_ManObjNum(p); i++ )
+    {
+        if ( p->pSibls[i] == 0 )
+            continue;
+        if ( p->pReprs[i].iRepr != GIA_VOID )
+            continue;
+        for ( iObj = p->pSibls[i]; iObj; iObj = p->pSibls[iObj] )
+            p->pReprs[iObj].iRepr = i;
+    }
+    ABC_FREE( p->pNexts );
+    p->pNexts = Gia_ManDeriveNexts( p );
+}
+
 /**Function*************************************************************
 
   Synopsis    []