diff --git a/src/js/static-filtering-parser.js b/src/js/static-filtering-parser.js
index 34828bc7a..491cf0368 100644
--- a/src/js/static-filtering-parser.js
+++ b/src/js/static-filtering-parser.js
@@ -1299,6 +1299,7 @@ export class AstFilterParser {
         let modifierType = 0;
         let requestTypeCount = 0;
         let unredirectableTypeCount = 0;
+        let badfilter = false;
         for ( let i = 0, n = this.nodeTypeRegisterPtr; i < n; i++ ) {
             const type = this.nodeTypeRegister[i];
             const targetNode = this.nodeTypeLookupTable[type];
@@ -1322,6 +1323,8 @@ export class AstFilterParser {
                     realBad = hasValue;
                     break;
                 case NODE_TYPE_NET_OPTION_NAME_BADFILTER:
+                    badfilter = true;
+                    /* falls through */
                 case NODE_TYPE_NET_OPTION_NAME_NOOP:
                     realBad = isNegated || hasValue;
                     break;
@@ -1462,6 +1465,9 @@ export class AstFilterParser {
                 this.addFlags(AST_FLAG_HAS_ERROR);
             }
         }
+        const requiresTrustedSource = ( ) =>
+            this.options.trustedSource !== true &&
+            isException === false && badfilter === false;
         switch ( modifierType ) {
             case NODE_TYPE_NET_OPTION_NAME_CNAME:
                 realBad = abstractTypeCount || behaviorTypeCount || requestTypeCount;
@@ -1489,7 +1495,7 @@ export class AstFilterParser {
             case NODE_TYPE_NET_OPTION_NAME_REPLACE: {
                 realBad = abstractTypeCount || behaviorTypeCount || unredirectableTypeCount;
                 if ( realBad ) { break; }
-                if ( isException !== true && this.options.trustedSource !== true ) {
+                if ( requiresTrustedSource() ) {
                     this.astError = AST_ERROR_UNTRUSTED_SOURCE;
                     realBad = true;
                     break;
@@ -1504,7 +1510,7 @@ export class AstFilterParser {
             case NODE_TYPE_NET_OPTION_NAME_URLTRANSFORM: {
                 realBad = abstractTypeCount || behaviorTypeCount || unredirectableTypeCount;
                 if ( realBad ) { break; }
-                if ( isException !== true && this.options.trustedSource !== true ) {
+                if ( requiresTrustedSource() ) {
                     this.astError = AST_ERROR_UNTRUSTED_SOURCE;
                     realBad = true;
                     break;