diff --git a/common/json-schema-to-grammar.cpp b/common/json-schema-to-grammar.cpp
index 881eb49e3..dadc18c8b 100644
--- a/common/json-schema-to-grammar.cpp
+++ b/common/json-schema-to-grammar.cpp
@@ -611,7 +611,7 @@ private:
             }
             return join_seq();
         };
-        return _add_rule(name, "\"\\\"\" " + to_rule(transform()) + " \"\\\"\" space");
+        return _add_rule(name, "\"\\\"\" (" + to_rule(transform()) + ") \"\\\"\" space");
     }
 
     /*
diff --git a/examples/json_schema_to_grammar.py b/examples/json_schema_to_grammar.py
index a8779bf3b..fc9f0097f 100755
--- a/examples/json_schema_to_grammar.py
+++ b/examples/json_schema_to_grammar.py
@@ -540,7 +540,7 @@ class SchemaConverter:
         return self._add_rule(
             name,
             to_rule(transform()) if self._raw_pattern \
-                else "\"\\\"\" " + to_rule(transform()) + " \"\\\"\" space")
+                else "\"\\\"\" (" + to_rule(transform()) + ") \"\\\"\" space")
 
 
     def _resolve_ref(self, ref):
diff --git a/examples/server/public/json-schema-to-grammar.mjs b/examples/server/public/json-schema-to-grammar.mjs
index 7267f3f9c..e67bb15c1 100644
--- a/examples/server/public/json-schema-to-grammar.mjs
+++ b/examples/server/public/json-schema-to-grammar.mjs
@@ -529,7 +529,7 @@ export class SchemaConverter {
       return joinSeq();
     };
 
-    return this._addRule(name, "\"\\\"\" " + toRule(transform()) + " \"\\\"\" space")
+    return this._addRule(name, "\"\\\"\" (" + toRule(transform()) + ") \"\\\"\" space")
   }
 
   _notStrings(strings) {
diff --git a/tests/test-json-schema-to-grammar.cpp b/tests/test-json-schema-to-grammar.cpp
index 3a89598a8..9d2db91f5 100755
--- a/tests/test-json-schema-to-grammar.cpp
+++ b/tests/test-json-schema-to-grammar.cpp
@@ -696,7 +696,7 @@ static void test_all(const std::string & lang, std::function<void(const TestCase
             "pattern": "^abc?d*efg+(hij)?kl$"
         })""",
         R"""(
-            root ::= "\"" "ab" "c"? "d"* "ef" "g"+ ("hij")? "kl" "\"" space
+            root ::= "\"" ("ab" "c"? "d"* "ef" "g"+ ("hij")? "kl") "\"" space
             space ::= | " " | "\n" [ \t]{0,20}
         )"""
     });
@@ -709,7 +709,7 @@ static void test_all(const std::string & lang, std::function<void(const TestCase
             "pattern": "^\\[\\]\\{\\}\\(\\)\\|\\+\\*\\?$"
         })""",
         R"""(
-            root ::= "\"" "[]{}()|+*?" "\"" space
+            root ::= "\"" ("[]{}()|+*?") "\"" space
             space ::= | " " | "\n" [ \t]{0,20}
         )"""
     });
@@ -722,7 +722,20 @@ static void test_all(const std::string & lang, std::function<void(const TestCase
             "pattern": "^\"$"
         })""",
         R"""(
-            root ::= "\"" "\"" "\"" space
+            root ::= "\"" ("\"") "\"" space
+            space ::= | " " | "\n" [ \t]{0,20}
+        )"""
+    });
+
+    test({
+        SUCCESS,
+        "regexp with top-level alternation",
+        R"""({
+            "type": "string",
+            "pattern": "^A|B|C|D$"
+        })""",
+        R"""(
+            root ::= "\"" ("A" | "B" | "C" | "D") "\"" space
             space ::= | " " | "\n" [ \t]{0,20}
         )"""
     });
@@ -736,7 +749,7 @@ static void test_all(const std::string & lang, std::function<void(const TestCase
         })""",
         R"""(
             dot ::= [^\x0A\x0D]
-            root ::= "\"" ("(" root-1{1,3} ")")? root-1{3,3} "-" root-1{4,4} " " "a"{3,5} "nd" dot dot dot "\"" space
+            root ::= "\"" (("(" root-1{1,3} ")")? root-1{3,3} "-" root-1{4,4} " " "a"{3,5} "nd" dot dot dot) "\"" space
             root-1 ::= [0-9]
             space ::= | " " | "\n" [ \t]{0,20}
         )"""