diff --git a/iguana/dPoW.h b/iguana/dPoW.h
index 2f0736c9a..a43ce93b8 100755
--- a/iguana/dPoW.h
+++ b/iguana/dPoW.h
@@ -99,7 +99,7 @@ struct dpow_block
     uint64_t recvmask,bestmask;
     struct dpow_entry notaries[DPOW_MAXRELAYS];
     uint32_t state,timestamp,waiting,sigcrcs[2],txidcrcs[2],utxocrcs[2];
-    int32_t height,numnotaries,completed,minsigs,duration,numratified,isratify;
+    int32_t height,numnotaries,completed,minsigs,duration,numratified,isratify,require0;
     int8_t bestk;
     cJSON *ratified;
     uint8_t ratified_pubkeys[DPOW_MAXRELAYS][33]; char handles[DPOW_MAXRELAYS][32];
diff --git a/iguana/dpow/dpow_fsm.c b/iguana/dpow/dpow_fsm.c
index 2293c35e7..6580ad2fe 100755
--- a/iguana/dpow/dpow_fsm.c
+++ b/iguana/dpow/dpow_fsm.c
@@ -506,6 +506,7 @@ void dpow_statemachinestart(void *ptr)
                             destprevvout0 = jint(item,"destprevvout0");
                             srcprevtxid0 = jbits256(item,"srcprevtxid0");
                             srcprevvout0 = jint(item,"srcprevvout0");
+                            bp->require0 = 1;
                         }
                     }
                     else
diff --git a/iguana/dpow/dpow_tx.c b/iguana/dpow/dpow_tx.c
index 905419af2..82c593600 100755
--- a/iguana/dpow/dpow_tx.c
+++ b/iguana/dpow/dpow_tx.c
@@ -15,9 +15,10 @@
 
 uint64_t dpow_lastk_mask(struct dpow_block *bp,int8_t *lastkp)
 {
-    int32_t j,m,k; uint64_t mask = 0;
+    int32_t j,m,k; uint64_t mask = bp->require0;
     *lastkp = -1;
-    for (j=m=0; j<bp->numnotaries; j++)
+    m = bp->require0;
+    for (j=0; j<bp->numnotaries; j++)
     {
         k = DPOW_MODIND(bp,j);//((bp->height % bp->numnotaries) + j) % bp->numnotaries;
         if ( bits256_nonz(bp->notaries[k].src.prev_hash) != 0 && bits256_nonz(bp->notaries[k].dest.prev_hash) != 0 )
@@ -47,9 +48,10 @@ int32_t dpow_bestk(struct dpow_block *bp,uint64_t *maskp)
 
 uint64_t dpow_maskmin(uint64_t refmask,struct dpow_block *bp,int8_t *lastkp)
 {
-    int32_t j,m,k; uint64_t bestmask,mask;
-    bestmask = mask = 0;
-    for (j=m=0; j<bp->numnotaries; j++)
+    int32_t j,m,k; uint64_t bestmask,mask = bp->require0;
+    bestmask = 0;
+    m = bp->require0;
+    for (j=0; j<bp->numnotaries; j++)
     {
         k = DPOW_MODIND(bp,j);
         if ( bits256_nonz(bp->notaries[k].src.prev_hash) != 0 && bits256_nonz(bp->notaries[k].dest.prev_hash) != 0 )