diff --git a/src/detect-engine-build.c b/src/detect-engine-build.c
index 604164b21c15..0c07150e696e 100644
--- a/src/detect-engine-build.c
+++ b/src/detect-engine-build.c
@@ -960,7 +960,6 @@ static int RulesGroupByProto(DetectEngineCtx *de_ctx)
 {
     Signature *s = de_ctx->sig_list;
 
-    uint32_t max_idx = 0;
     SigGroupHead *sgh_ts[256] = {NULL};
     SigGroupHead *sgh_tc[256] = {NULL};
 
@@ -979,15 +978,12 @@ static int RulesGroupByProto(DetectEngineCtx *de_ctx)
 
             if (s->flags & SIG_FLAG_TOCLIENT) {
                 SigGroupHeadAppendSig(de_ctx, &sgh_tc[p], s);
-                max_idx = s->num;
             }
             if (s->flags & SIG_FLAG_TOSERVER) {
                 SigGroupHeadAppendSig(de_ctx, &sgh_ts[p], s);
-                max_idx = s->num;
             }
         }
     }
-    SCLogDebug("max_idx %u", max_idx);
 
     /* lets look at deduplicating this list */
     SigGroupHeadHashFree(de_ctx);
@@ -1009,8 +1005,8 @@ static int RulesGroupByProto(DetectEngineCtx *de_ctx)
         if (lookup_sgh == NULL) {
             SCLogDebug("proto group %d sgh %p is the original", p, sgh_ts[p]);
 
-            SigGroupHeadSetSigCnt(sgh_ts[p], max_idx);
-            SigGroupHeadBuildMatchArray(de_ctx, sgh_ts[p], max_idx);
+            SigGroupHeadSetSigCnt(sgh_ts[p], 0);
+            SigGroupHeadBuildMatchArray(de_ctx, sgh_ts[p], 0);
 
             SigGroupHeadHashAdd(de_ctx, sgh_ts[p]);
             SigGroupHeadStore(de_ctx, sgh_ts[p]);
@@ -1041,8 +1037,8 @@ static int RulesGroupByProto(DetectEngineCtx *de_ctx)
         if (lookup_sgh == NULL) {
             SCLogDebug("proto group %d sgh %p is the original", p, sgh_tc[p]);
 
-            SigGroupHeadSetSigCnt(sgh_tc[p], max_idx);
-            SigGroupHeadBuildMatchArray(de_ctx, sgh_tc[p], max_idx);
+            SigGroupHeadSetSigCnt(sgh_tc[p], 0);
+            SigGroupHeadBuildMatchArray(de_ctx, sgh_tc[p], 0);
 
             SigGroupHeadHashAdd(de_ctx, sgh_tc[p]);
             SigGroupHeadStore(de_ctx, sgh_tc[p]);
@@ -1129,7 +1125,8 @@ static int RuleSetWhitelist(Signature *s)
     return wl;
 }
 
-int CreateGroupedPortList(DetectEngineCtx *de_ctx, DetectPort *port_list, DetectPort **newhead, uint32_t unique_groups, int (*CompareFunc)(DetectPort *, DetectPort *), uint32_t max_idx);
+int CreateGroupedPortList(DetectEngineCtx *de_ctx, DetectPort *port_list, DetectPort **newhead,
+        uint32_t unique_groups, int (*CompareFunc)(DetectPort *, DetectPort *));
 int CreateGroupedPortListCmpCnt(DetectPort *a, DetectPort *b);
 
 static DetectPort *RulesGroupByPorts(DetectEngineCtx *de_ctx, uint8_t ipproto, uint32_t direction)
@@ -1139,7 +1136,6 @@ static DetectPort *RulesGroupByPorts(DetectEngineCtx *de_ctx, uint8_t ipproto, u
      *         that belong to the SGH. */
     DetectPortHashInit(de_ctx);
 
-    uint32_t max_idx = 0;
     const Signature *s = de_ctx->sig_list;
     DetectPort *list = NULL;
     while (s) {
@@ -1198,7 +1194,6 @@ static DetectPort *RulesGroupByPorts(DetectEngineCtx *de_ctx, uint8_t ipproto, u
 
             p = p->next;
         }
-        max_idx = s->num;
     next:
         s = s->next;
     }
@@ -1223,7 +1218,7 @@ static DetectPort *RulesGroupByPorts(DetectEngineCtx *de_ctx, uint8_t ipproto, u
     DetectPort *newlist = NULL;
     uint16_t groupmax = (direction == SIG_FLAG_TOCLIENT) ? de_ctx->max_uniq_toclient_groups :
                                                            de_ctx->max_uniq_toserver_groups;
-    CreateGroupedPortList(de_ctx, list, &newlist, groupmax, CreateGroupedPortListCmpCnt, max_idx);
+    CreateGroupedPortList(de_ctx, list, &newlist, groupmax, CreateGroupedPortListCmpCnt);
     list = newlist;
 
     /* step 4: deduplicate the SGH's */
@@ -1243,8 +1238,8 @@ static DetectPort *RulesGroupByPorts(DetectEngineCtx *de_ctx, uint8_t ipproto, u
         if (lookup_sgh == NULL) {
             SCLogDebug("port group %p sgh %p is the original", iter, iter->sh);
 
-            SigGroupHeadSetSigCnt(iter->sh, max_idx);
-            SigGroupHeadBuildMatchArray(de_ctx, iter->sh, max_idx);
+            SigGroupHeadSetSigCnt(iter->sh, 0);
+            SigGroupHeadBuildMatchArray(de_ctx, iter->sh, 0);
             SigGroupHeadSetProtoAndDirection(iter->sh, ipproto, direction);
             SigGroupHeadHashAdd(de_ctx, iter->sh);
             SigGroupHeadStore(de_ctx, iter->sh);
@@ -1541,7 +1536,8 @@ int CreateGroupedPortListCmpCnt(DetectPort *a, DetectPort *b)
  *  The joingr is meant to be a catch all.
  *
  */
-int CreateGroupedPortList(DetectEngineCtx *de_ctx, DetectPort *port_list, DetectPort **newhead, uint32_t unique_groups, int (*CompareFunc)(DetectPort *, DetectPort *), uint32_t max_idx)
+int CreateGroupedPortList(DetectEngineCtx *de_ctx, DetectPort *port_list, DetectPort **newhead,
+        uint32_t unique_groups, int (*CompareFunc)(DetectPort *, DetectPort *))
 {
     DetectPort *tmplist = NULL, *joingr = NULL;
     char insert = 0;
@@ -1560,8 +1556,7 @@ int CreateGroupedPortList(DetectEngineCtx *de_ctx, DetectPort *port_list, Detect
         list->next = NULL;
 
         groups++;
-
-        SigGroupHeadSetSigCnt(list->sh, max_idx);
+        SigGroupHeadSetSigCnt(list->sh, 0);
 
         /* insert it */
         DetectPort *tmpgr = tmplist, *prevtmpgr = NULL;
diff --git a/src/detect-engine-siggroup.c b/src/detect-engine-siggroup.c
index 4fadaac5c013..9bc992cb894a 100644
--- a/src/detect-engine-siggroup.c
+++ b/src/detect-engine-siggroup.c
@@ -347,7 +347,7 @@ int SigGroupHeadAppendSig(const DetectEngineCtx *de_ctx, SigGroupHead **sgh,
 
     /* enable the sig in the bitarray */
     (*sgh)->init->sig_array[s->num / 8] |= 1 << (s->num % 8);
-
+    (*sgh)->init->max_sig_id = MAX(s->num, (*sgh)->init->max_sig_id);
     return 0;
 
 error:
@@ -405,6 +405,8 @@ int SigGroupHeadCopySigs(DetectEngineCtx *de_ctx, SigGroupHead *src, SigGroupHea
     if (src->init->score)
         (*dst)->init->score = MAX((*dst)->init->score, src->init->score);
 
+    if (src->init->max_sig_id)
+        (*dst)->init->max_sig_id = MAX((*dst)->init->max_sig_id, src->init->max_sig_id);
     return 0;
 
 error:
@@ -422,9 +424,9 @@ int SigGroupHeadCopySigs(DetectEngineCtx *de_ctx, SigGroupHead *src, SigGroupHea
 void SigGroupHeadSetSigCnt(SigGroupHead *sgh, uint32_t max_idx)
 {
     uint32_t sig;
-
+    sgh->init->max_sig_id = MAX(max_idx, sgh->init->max_sig_id);
     sgh->init->sig_cnt = 0;
-    for (sig = 0; sig < max_idx + 1; sig++) {
+    for (sig = 0; sig < sgh->init->max_sig_id + 1; sig++) {
         if (sgh->init->sig_array[sig / 8] & (1 << (sig % 8)))
             sgh->init->sig_cnt++;
     }
@@ -492,12 +494,13 @@ int SigGroupHeadBuildMatchArray(DetectEngineCtx *de_ctx, SigGroupHead *sgh,
         return 0;
 
     BUG_ON(sgh->init->match_array != NULL);
+    sgh->init->max_sig_id = MAX(sgh->init->max_sig_id, max_idx);
 
     sgh->init->match_array = SCCalloc(sgh->init->sig_cnt, sizeof(Signature *));
     if (sgh->init->match_array == NULL)
         return -1;
 
-    for (sig = 0; sig < max_idx + 1; sig++) {
+    for (sig = 0; sig < sgh->init->max_sig_id + 1; sig++) {
         if (!(sgh->init->sig_array[(sig / 8)] & (1 << (sig % 8))) )
             continue;
 
diff --git a/src/detect.h b/src/detect.h
index 0fc5d21fb1d8..0707d8a5b211 100644
--- a/src/detect.h
+++ b/src/detect.h
@@ -1419,6 +1419,7 @@ typedef struct SigGroupHeadInitData_ {
     uint8_t protos[256];    /**< proto(s) this sgh is for */
     uint32_t direction;     /**< set to SIG_FLAG_TOSERVER, SIG_FLAG_TOCLIENT or both */
     int score;              /**< try to make this group a unique one */
+    uint32_t max_sig_id;    /**< max signature idx for this sgh */
 
     MpmCtx **app_mpms;
     MpmCtx **pkt_mpms;
@@ -1434,9 +1435,6 @@ typedef struct SigGroupHeadInitData_ {
 
     /** Array with sig ptrs... size is sig_cnt * sizeof(Signature *) */
     Signature **match_array;
-
-    /* port ptr */
-    struct DetectPort_ *port;
 } SigGroupHeadInitData;
 
 /** \brief Container for matching data for a signature group */