diff --git a/VERSION b/VERSION
index 3580c9fa..aded7447 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-8.3.663
+8.3.664
diff --git a/extract/ExtHier.c b/extract/ExtHier.c
index 09df8ae5..5321d952 100644
--- a/extract/ExtHier.c
+++ b/extract/ExtHier.c
@@ -115,23 +115,91 @@ bool extTestNMInteract(Tile *t1, TileType di1, Tile *t2, TileType di2)
 
 /*
  *----------------------------------------------------------------------
- * extHierSubShieldFunc --						
+ * extHierSubInteractFunc --						
  *
- *	Simple callback function for extHierSubstrate() that halts the
- *	search if any substrate shield type is found in the search area
+ *	Simple callback function for extHierSubShielfFunc() that halts
+ *	the search if any type connecting to substrate is found in
+ *	the area.
+ *
+ * Results:  1 to stop the search.
+ *
+ * Side effects:  None.
  *
  *----------------------------------------------------------------------
  */
 
 int
-extHierSubShieldFunc(tile, dinfo, clientdata)
-    Tile *tile;			/* (unused) */
-    TileType dinfo;		/* (unused) */
-    ClientData clientdata;	/* (unused) */
+extHierSubInteractFunc(tile, dinfo, clientdata)
+    Tile *tile;			/* unused */
+    TileType dinfo;		/* unused */
+    ClientData clientdata;	/* unused */
 {
     return 1;
 }
 
+/*
+ *----------------------------------------------------------------------
+ * extHierSubShieldFunc --						
+ *
+ *	Callback function for extHierSubstrate() that halts the search
+ *	if any substrate shield type is found in the search area.  To
+ *	avoid flagging substrate shields that overlap the search area
+ *	but do not interact with the cell, check the area of the
+ *	substrate shield for device types that connect to substrate
+ *	(ExtCurStyle->exts_subsDevTypes).  If something is found, then
+ *	return 1 immediately to stop the search.
+ *
+ * Results:  1 if an interacting substrate shield is found, 0 otherwise.
+ *
+ * Side effects:  None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+extHierSubShieldFunc(tile, dinfo, use)
+    Tile *tile;
+    TileType dinfo;
+    CellUse *use;
+{
+    Rect r, rsub;
+    int  pNum;
+    TileType ttype;
+    CellDef *subdef;
+    Transform t;
+
+    if (IsSplit(tile))
+    {
+	ttype = TiGetLeftType(tile);
+	if (!TTMaskHasType(&ExtCurStyle->exts_globSubstrateShieldTypes, ttype))
+	    ttype = TiGetRightType(tile);
+    }
+    else
+	ttype = TiGetTypeExact(tile);
+
+    TiToRect(tile, &r);
+
+    /* Convert area of tile to the coordinates of the cell "subdef", which is
+     * a child of the cell containing "tile".
+     */
+    subdef = use->cu_def;
+    GeoInvertTrans(&use->cu_transform, &t);
+    GeoTransRect(&t, &r, &rsub);
+
+    for (pNum = PL_TECHDEPBASE; pNum < DBNumPlanes; pNum++)
+    {
+	if (TTMaskIntersect(&DBPlaneTypes[pNum], &ExtCurStyle->exts_subsDevTypes))
+	{
+	    if (DBSrPaintNMArea((Tile *)NULL,
+			subdef->cd_planes[pNum], dinfo, &rsub,
+			&ExtCurStyle->exts_subsDevTypes,
+			extHierSubInteractFunc, (ClientData)NULL) == 1)
+		return 1;
+	}
+    }
+    return 0;
+}
+
 /*
  *----------------------------------------------------------------------
  * extHierSubstrate --
@@ -229,7 +297,7 @@ extHierSubstrate(ha, use, x, y)
     	    if (DBSrPaintArea((Tile *) NULL,
 			def->cd_planes[pNum], &subArea,
 			&ExtCurStyle->exts_globSubstrateShieldTypes,
-			extHierSubShieldFunc, (ClientData)NULL) != 0)
+			extHierSubShieldFunc, PTR2CD(use)) != 0)
     	    {
     		freeMagic(nodeList);
     		ExtResetTiles(use->cu_def, CLIENTDEFAULT);
diff --git a/extract/ExtTech.c b/extract/ExtTech.c
index e4884054..b11d0bd9 100644
--- a/extract/ExtTech.c
+++ b/extract/ExtTech.c
@@ -836,6 +836,7 @@ extTechStyleInit(style)
 
     style->exts_sidePlanes = style->exts_overlapPlanes = 0;
     TTMaskZero(&style->exts_deviceMask);
+    TTMaskZero(&style->exts_subsDevTypes);
     style->exts_activeTypes = DBAllButSpaceAndDRCBits;
 
     for (r = 0; r < NP; r++)
@@ -2355,6 +2356,9 @@ ExtTechLine(sectionName, argc, argv)
 	    }
 
 	    TTMaskSetMask(&ExtCurStyle->exts_deviceMask, &types1);
+	    if (!TTMaskIsZero(&subsTypes))
+		TTMaskSetMask(&ExtCurStyle->exts_subsDevTypes, &types1);
+
 	    for (t = TT_TECHDEPBASE; t < DBNumTypes; t++)
 		if (TTMaskHasType(&types1, t))
 		{
@@ -2380,6 +2384,7 @@ ExtTechLine(sectionName, argc, argv)
 
 		    devptr->exts_next = ExtCurStyle->exts_device[t];
 		    ExtCurStyle->exts_device[t] = devptr;
+
 #ifdef ARIEL
 		    {
 			int z;
@@ -2867,6 +2872,8 @@ ExtTechLine(sectionName, argc, argv)
 	    }
 
 	    TTMaskSetMask(&ExtCurStyle->exts_deviceMask, &types1);
+	    if (!TTMaskIsZero(&subsTypes))
+		TTMaskSetMask(&ExtCurStyle->exts_subsDevTypes, &types1);
 
 	    for (t = TT_TECHDEPBASE; t < DBNumTypes; t++)
 	    {
diff --git a/extract/extractInt.h b/extract/extractInt.h
index 97cdcf05..7ea28adc 100644
--- a/extract/extractInt.h
+++ b/extract/extractInt.h
@@ -626,6 +626,13 @@ typedef struct extstyle
      */
     TileTypeBitMask	 exts_deviceConn[NT];
 
+    /*
+     * List of device types which connect to a substrate type.  This
+     * distinguishes between devices that make a connection to substrate
+     * (e.g., FETs) and those that don't (e.g., MiM caps, metal resistors).
+     */
+    TileTypeBitMask	exts_subsDevTypes;
+
     /*
      * Set of types to be considered for extraction.  Types not in
      * this list cannot be nodes (e.g., implant layers)
diff --git a/resis/ResMain.c b/resis/ResMain.c
index 1e40c73f..5c71b2a2 100644
--- a/resis/ResMain.c
+++ b/resis/ResMain.c
@@ -1492,7 +1492,7 @@ ResExtractNet(node, resisdata, cellname)
 	resDevTerm *resdevList, *resdevNext;
 
 	resdevList = (resDevTerm *)HashGetValue(he);
-	while (resdevList)
+	if (resdevList)
 	{
 	    /* Diagnostic */
 	    Tile *tp;
@@ -1501,9 +1501,12 @@ ResExtractNet(node, resisdata, cellname)
 			(resdevList->rdt_term < 0) ? "Substrate" : "Terminal",
 			tp->ti_ll.p_x, tp->ti_ll.p_y);
 
-	    resdevNext = resdevList->rdt_next;
-	    freeMagic((char *)resdevList);
-	    resdevList = resdevNext;
+	    while (resdevList)
+	    {
+		resdevNext = resdevList->rdt_next;
+		freeMagic((char *)resdevList);
+		resdevList = resdevNext;
+	    }
 	}
     }
     HashKill(&DevNodeTable);
diff --git a/resis/ResReadExt.c b/resis/ResReadExt.c
index 7bd95c09..9ee11ef2 100644
--- a/resis/ResReadExt.c
+++ b/resis/ResReadExt.c
@@ -737,7 +737,7 @@ ResReadDevice(int argc,
     char *argv[])
 {
     RDev	*device;
-    int		rvalue, i, j, k, w, l;
+    int		rvalue, i, j, k, w, l, n;
     ExtDevice	*devptr;
     TileType	ttype;
     HashEntry	*entry;
@@ -791,13 +791,25 @@ ResReadDevice(int argc,
      * arbitrary number of terminals.
      */
 
-    if (strcmp(argv[i], "None"))
+    /* See code in extflat/EFbuild.c:  Devices do not necessarily
+     * declare a substrate terminal.  This can be determined by
+     * noting that all terminals other than the substrate come in
+     * triplets of arguments, so if the remaining count of arguments
+     * is divisible by 3, then there is no substrate node, and if
+     * there is a remainder of 1, then there is.  It would probably
+     * be simpler if all devices just put "None" in this position.
+     */
+    n = argc - i;
+    if ((n % 3) == 1)	/* Device has a substrate argument */
     {
-	entry = HashFind(&ResNodeTable, argv[i]);
-	device->subs = (ResExtNode *)HashGetValue(entry);
-	ResNodeAddDevice(device->subs, device, SUBS);
+	if (strcmp(argv[i], "None"))
+	{
+	    entry = HashFind(&ResNodeTable, argv[i]);
+	    device->subs = (ResExtNode *)HashGetValue(entry);
+	    ResNodeAddDevice(device->subs, device, SUBS);
+	}
+	i++;
     }
-    i++;
     entry = HashFind(&ResNodeTable, argv[i]);
     device->gate = (ResExtNode *)HashGetValue(entry);
     device->rs_gattr = StrDup((char **)NULL, argv[i + 2]);