diff --git a/ext/fts3/fts3_expr.c b/ext/fts3/fts3_expr.c
index d7cabd9919..788e5021ec 100644
--- a/ext/fts3/fts3_expr.c
+++ b/ext/fts3/fts3_expr.c
@@ -793,125 +793,151 @@ static int fts3ExprBalance(Fts3Expr **pp, int nMaxDepth){
     rc = SQLITE_ERROR;
   }
 
-  if( rc==SQLITE_OK && (eType==FTSQUERY_AND || eType==FTSQUERY_OR) ){
-    Fts3Expr **apLeaf;
-    apLeaf = (Fts3Expr **)sqlite3_malloc(sizeof(Fts3Expr *) * nMaxDepth);
-    if( 0==apLeaf ){
-      rc = SQLITE_NOMEM;
-    }else{
-      memset(apLeaf, 0, sizeof(Fts3Expr *) * nMaxDepth);
-    }
-
-    if( rc==SQLITE_OK ){
-      int i;
-      Fts3Expr *p;
-
-      /* Set $p to point to the left-most leaf in the tree of eType nodes. */
-      for(p=pRoot; p->eType==eType; p=p->pLeft){
-        assert( p->pParent==0 || p->pParent->pLeft==p );
-        assert( p->pLeft && p->pRight );
-      }
-
-      /* This loop runs once for each leaf in the tree of eType nodes. */
-      while( 1 ){
-        int iLvl;
-        Fts3Expr *pParent = p->pParent;     /* Current parent of p */
-
-        assert( pParent==0 || pParent->pLeft==p );
-        p->pParent = 0;
-        if( pParent ){
-          pParent->pLeft = 0;
-        }else{
-          pRoot = 0;
-        }
-        rc = fts3ExprBalance(&p, nMaxDepth-1);
-        if( rc!=SQLITE_OK ) break;
-
-        for(iLvl=0; p && iLvl<nMaxDepth; iLvl++){
-          if( apLeaf[iLvl]==0 ){
-            apLeaf[iLvl] = p;
-            p = 0;
-          }else{
-            assert( pFree );
-            pFree->pLeft = apLeaf[iLvl];
-            pFree->pRight = p;
-            pFree->pLeft->pParent = pFree;
-            pFree->pRight->pParent = pFree;
-
-            p = pFree;
-            pFree = pFree->pParent;
-            p->pParent = 0;
-            apLeaf[iLvl] = 0;
-          }
-        }
-        if( p ){
-          sqlite3Fts3ExprFree(p);
-          rc = SQLITE_TOOBIG;
-          break;
-        }
-
-        /* If that was the last leaf node, break out of the loop */
-        if( pParent==0 ) break;
-
-        /* Set $p to point to the next leaf in the tree of eType nodes */
-        for(p=pParent->pRight; p->eType==eType; p=p->pLeft);
-
-        /* Remove pParent from the original tree. */
-        assert( pParent->pParent==0 || pParent->pParent->pLeft==pParent );
-        pParent->pRight->pParent = pParent->pParent;
-        if( pParent->pParent ){
-          pParent->pParent->pLeft = pParent->pRight;
-        }else{
-          assert( pParent==pRoot );
-          pRoot = pParent->pRight;
-        }
-
-        /* Link pParent into the free node list. It will be used as an
-        ** internal node of the new tree.  */
-        pParent->pParent = pFree;
-        pFree = pParent;
+  if( rc==SQLITE_OK ){
+    if( (eType==FTSQUERY_AND || eType==FTSQUERY_OR) ){
+      Fts3Expr **apLeaf;
+      apLeaf = (Fts3Expr **)sqlite3_malloc(sizeof(Fts3Expr *) * nMaxDepth);
+      if( 0==apLeaf ){
+        rc = SQLITE_NOMEM;
+      }else{
+        memset(apLeaf, 0, sizeof(Fts3Expr *) * nMaxDepth);
       }
 
       if( rc==SQLITE_OK ){
-        p = 0;
-        for(i=0; i<nMaxDepth; i++){
-          if( apLeaf[i] ){
-            if( p==0 ){
-              p = apLeaf[i];
-              p->pParent = 0;
+        int i;
+        Fts3Expr *p;
+
+        /* Set $p to point to the left-most leaf in the tree of eType nodes. */
+        for(p=pRoot; p->eType==eType; p=p->pLeft){
+          assert( p->pParent==0 || p->pParent->pLeft==p );
+          assert( p->pLeft && p->pRight );
+        }
+
+        /* This loop runs once for each leaf in the tree of eType nodes. */
+        while( 1 ){
+          int iLvl;
+          Fts3Expr *pParent = p->pParent;     /* Current parent of p */
+
+          assert( pParent==0 || pParent->pLeft==p );
+          p->pParent = 0;
+          if( pParent ){
+            pParent->pLeft = 0;
+          }else{
+            pRoot = 0;
+          }
+          rc = fts3ExprBalance(&p, nMaxDepth-1);
+          if( rc!=SQLITE_OK ) break;
+
+          for(iLvl=0; p && iLvl<nMaxDepth; iLvl++){
+            if( apLeaf[iLvl]==0 ){
+              apLeaf[iLvl] = p;
+              p = 0;
             }else{
-              assert( pFree!=0 );
+              assert( pFree );
+              pFree->pLeft = apLeaf[iLvl];
               pFree->pRight = p;
-              pFree->pLeft = apLeaf[i];
               pFree->pLeft->pParent = pFree;
               pFree->pRight->pParent = pFree;
 
               p = pFree;
               pFree = pFree->pParent;
               p->pParent = 0;
+              apLeaf[iLvl] = 0;
             }
           }
+          if( p ){
+            sqlite3Fts3ExprFree(p);
+            rc = SQLITE_TOOBIG;
+            break;
+          }
+
+          /* If that was the last leaf node, break out of the loop */
+          if( pParent==0 ) break;
+
+          /* Set $p to point to the next leaf in the tree of eType nodes */
+          for(p=pParent->pRight; p->eType==eType; p=p->pLeft);
+
+          /* Remove pParent from the original tree. */
+          assert( pParent->pParent==0 || pParent->pParent->pLeft==pParent );
+          pParent->pRight->pParent = pParent->pParent;
+          if( pParent->pParent ){
+            pParent->pParent->pLeft = pParent->pRight;
+          }else{
+            assert( pParent==pRoot );
+            pRoot = pParent->pRight;
+          }
+
+          /* Link pParent into the free node list. It will be used as an
+          ** internal node of the new tree.  */
+          pParent->pParent = pFree;
+          pFree = pParent;
         }
-        pRoot = p;
-      }else{
-        /* An error occurred. Delete the contents of the apLeaf[] array 
-        ** and pFree list. Everything else is cleaned up by the call to
-        ** sqlite3Fts3ExprFree(pRoot) below.  */
-        Fts3Expr *pDel;
-        for(i=0; i<nMaxDepth; i++){
-          sqlite3Fts3ExprFree(apLeaf[i]);
-        }
-        while( (pDel=pFree)!=0 ){
-          pFree = pDel->pParent;
-          sqlite3_free(pDel);
+
+        if( rc==SQLITE_OK ){
+          p = 0;
+          for(i=0; i<nMaxDepth; i++){
+            if( apLeaf[i] ){
+              if( p==0 ){
+                p = apLeaf[i];
+                p->pParent = 0;
+              }else{
+                assert( pFree!=0 );
+                pFree->pRight = p;
+                pFree->pLeft = apLeaf[i];
+                pFree->pLeft->pParent = pFree;
+                pFree->pRight->pParent = pFree;
+
+                p = pFree;
+                pFree = pFree->pParent;
+                p->pParent = 0;
+              }
+            }
+          }
+          pRoot = p;
+        }else{
+          /* An error occurred. Delete the contents of the apLeaf[] array 
+          ** and pFree list. Everything else is cleaned up by the call to
+          ** sqlite3Fts3ExprFree(pRoot) below.  */
+          Fts3Expr *pDel;
+          for(i=0; i<nMaxDepth; i++){
+            sqlite3Fts3ExprFree(apLeaf[i]);
+          }
+          while( (pDel=pFree)!=0 ){
+            pFree = pDel->pParent;
+            sqlite3_free(pDel);
+          }
         }
+
+        assert( pFree==0 );
+        sqlite3_free( apLeaf );
+      }
+    }else if( eType==FTSQUERY_NOT ){
+      Fts3Expr *pLeft = pRoot->pLeft;
+      Fts3Expr *pRight = pRoot->pRight;
+
+      pRoot->pLeft = 0;
+      pRoot->pRight = 0;
+      pLeft->pParent = 0;
+      pRight->pParent = 0;
+
+      rc = fts3ExprBalance(&pLeft, nMaxDepth-1);
+      if( rc==SQLITE_OK ){
+        rc = fts3ExprBalance(&pRight, nMaxDepth-1);
       }
 
-      assert( pFree==0 );
-      sqlite3_free( apLeaf );
+      if( rc!=SQLITE_OK ){
+        sqlite3Fts3ExprFree(pRight);
+        sqlite3Fts3ExprFree(pLeft);
+      }else{
+        assert( pLeft && pRight );
+        pRoot->pLeft = pLeft;
+        pLeft->pParent = pRoot;
+        pRoot->pRight = pRight;
+        pRight->pParent = pRoot;
+      }
     }
   }
-
+  
   if( rc!=SQLITE_OK ){
     sqlite3Fts3ExprFree(pRoot);
     pRoot = 0;
diff --git a/manifest b/manifest
index 30906a1cee..a6a5c2b408 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Add\sfts5txt2db.tcl,\sa\stool\sfor\screating\ssample\sfts4/5\sdatabases\sfrom\stext\sfiles.
-D 2015-10-05T11:57:09.832
+C Update\sfts3\sso\sthat\sexpressions\sto\sthe\sleft\sand\sright\sof\sa\sNOT\soperator\sare\sbalanced.\sThis\sprevents\srelatively\ssmall\sexpressions\s(a\sdozen\sterms\sor\sso)\sthat\sare\schildren\sof\sNOT\soperators\sfrom\striggering\sthe\s"expression\stree\sis\stoo\slarge"\serror.
+D 2015-10-05T15:39:45.681
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 2143eeef6d0cc26006ae5fc4bb242a4a8b973412
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -82,7 +82,7 @@ F ext/fts3/fts3.c e028eb13432f108d2e22cded019fc980700e4e00
 F ext/fts3/fts3.h 3a10a0af180d502cecc50df77b1b22df142817fe
 F ext/fts3/fts3Int.h c84125c666ee54cef6efce6ff64abb0d0e2f4535
 F ext/fts3/fts3_aux.c 9edc3655fcb287f0467d0a4b886a01c6185fe9f1
-F ext/fts3/fts3_expr.c 71c063da9c2a4167fb54aec089dd5ef33a58c9cb
+F ext/fts3/fts3_expr.c dfd571a24412779ac01f25c01d888c6ef7b2d0ef
 F ext/fts3/fts3_hash.c 29b986e43f4e9dd40110eafa377dc0d63c422c60
 F ext/fts3/fts3_hash.h 39cf6874dc239d6b4e30479b1975fe5b22a3caaf
 F ext/fts3/fts3_icu.c deb46f7020d87ea7a14a433fb7a7f4bef42a9652
@@ -704,7 +704,7 @@ F test/fts3drop.test 1b906e293d6773812587b3dc458cb9e8f3f0c297
 F test/fts3e.test 1f6c6ac9cc8b772ca256e6b22aaeed50c9350851
 F test/fts3expr.test 3401d47b229c4504424caf362cc4ff704cad4162
 F test/fts3expr2.test 18da930352e5693eaa163a3eacf96233b7290d1a
-F test/fts3expr3.test 9e91b8edbcb197bf2e92161aa7696446d96dce5f
+F test/fts3expr3.test c4d4a7d6327418428c96e0a3a1137c251b8dfbf8
 F test/fts3expr4.test e1be1248566f43c252d4404d52914f1fc4bfa065
 F test/fts3expr5.test f9abfffbf5e53d48a33e12a1e8f8ba2c551c9b49
 F test/fts3fault.test da49627b280b210ebc6657f76344c7851f10ce66
@@ -1391,7 +1391,7 @@ F tool/vdbe_profile.tcl 67746953071a9f8f2f668b73fe899074e2c6d8c1
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh 48bd54594752d5be3337f12c72f28d2080cb630b
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 41d17d9e24303aed6d549ea23c62b93bf2f71691
-R 5e8c1254946bcba6c019e513b206067f
+P 44f1ce30d1e446c9ee5f8bd8a62119e00356aa0e
+R 0954493ffc80fb341b0df1cab997ace8
 U dan
-Z 56785af9a4f39d2ef982f38c897a3388
+Z 52900cdc8d31460ed8eb8d6276be0e92
diff --git a/manifest.uuid b/manifest.uuid
index 8d0a492b28..a2a1d63f6e 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-44f1ce30d1e446c9ee5f8bd8a62119e00356aa0e
\ No newline at end of file
+d6b66cd7b89fbd964f798d160a34caac0ba7347a
\ No newline at end of file
diff --git a/test/fts3expr3.test b/test/fts3expr3.test
index a8d7319266..83c153218c 100644
--- a/test/fts3expr3.test
+++ b/test/fts3expr3.test
@@ -122,6 +122,8 @@ proc balanced_andor_tree {nEntry} {
   return $tree
 }
 
+if 1 {
+
 # Test that queries like "1 AND 2 AND 3 AND 4..." are transformed to 
 # balanced trees by FTS.
 #
@@ -202,5 +204,35 @@ do_faultsim_test fts3expr3-fault-1 -faults oom-* -body {
   faultsim_test_result [list 0 $::result]
 }
 
+}
+
+#-------------------------------------------------------------------
+
+foreach {tn expr res} {
+  1 {1 OR 2 OR 3 OR 4}           {OR {OR {P 1} {P 2}} {OR {P 3} {P 4}}} 
+  2 {1 OR (2 AND 3 AND 4 AND 5)} 
+    {OR {P 1} {AND {AND {P 2} {P 3}} {AND {P 4} {P 5}}}}
+  3 {(2 AND 3 AND 4 AND 5) OR 1} 
+    {OR {AND {AND {P 2} {P 3}} {AND {P 4} {P 5}}} {P 1}}
+
+  4 {1 AND (2 OR 3 OR 4 OR 5)} 
+    {AND {P 1} {OR {OR {P 2} {P 3}} {OR {P 4} {P 5}}}}
+  5 {(2 OR 3 OR 4 OR 5) AND 1} 
+    {AND {OR {OR {P 2} {P 3}} {OR {P 4} {P 5}}} {P 1}}
+
+  6 {(2 OR 3 OR 4 OR 5) NOT 1} 
+    {NOT {OR {OR {P 2} {P 3}} {OR {P 4} {P 5}}} {P 1}}
+
+  7 {1 NOT (2 OR 3 OR 4 OR 5)} 
+    {NOT {P 1} {OR {OR {P 2} {P 3}} {OR {P 4} {P 5}}}}
+
+  8 {(1 OR 2 OR 3 OR 4) NOT (5 AND 6 AND 7 AND 8)}
+    {NOT {OR {OR {P 1} {P 2}} {OR {P 3} {P 4}}} {AND {AND {P 5} {P 6}} {AND {P 7} {P 8}}}}
+} {
+  do_test 5.1.$tn {
+    test_fts3expr2 $expr
+  } $res
+}
+
 set sqlite_fts3_enable_parentheses 0
 finish_test