diff --git a/src/velum.ts b/src/velum.ts
index d8b8681..a2cd096 100644
--- a/src/velum.ts
+++ b/src/velum.ts
@@ -11,6 +11,66 @@ function escapeRegExp(value: string): string {
   return value.replace(/[.*+?^${}()|[\]\\]/g, "\\$&");
 }
 
+const BRACKET_PAIRS: Array<{ open: string; close: string }> = [
+  { open: "(", close: ")" },
+  { open: "[", close: "]" },
+  { open: "{", close: "}" },
+];
+
+function countChar(value: string, char: string): number {
+  let count = 0;
+  for (const c of value) if (c === char) count += 1;
+  return count;
+}
+
+function rebalanceBrackets(
+  text: string,
+  mapping: PlaceholderMapping,
+): { text: string; mapping: PlaceholderMapping } {
+  let resultText = text;
+  const resultMapping: PlaceholderMapping = {};
+
+  for (const [placeholder, entry] of Object.entries(mapping)) {
+    let original = entry.original;
+    let lead = "";
+    let trail = "";
+
+    let trimmed = true;
+    while (trimmed && original.length > 0) {
+      trimmed = false;
+      const pair = BRACKET_PAIRS.find((p) => original.startsWith(p.open));
+      if (pair && countChar(original, pair.open) > countChar(original, pair.close)) {
+        lead += original[0];
+        original = original.slice(1);
+        trimmed = true;
+      }
+    }
+
+    trimmed = true;
+    while (trimmed && original.length > 0) {
+      trimmed = false;
+      const pair = BRACKET_PAIRS.find((p) => original.endsWith(p.close));
+      if (pair && countChar(original, pair.close) > countChar(original, pair.open)) {
+        trail = original[original.length - 1] + trail;
+        original = original.slice(0, -1);
+        trimmed = true;
+      }
+    }
+
+    if (lead || trail) {
+      const escaped = escapeRegExp(placeholder);
+      resultText = resultText.replace(
+        new RegExp(escaped, "g"),
+        `${lead}${placeholder}${trail}`,
+      );
+    }
+
+    resultMapping[placeholder] = { ...entry, original };
+  }
+
+  return { text: resultText, mapping: resultMapping };
+}
+
 export function normalizePseudonymizeResponse(
   response: PseudonymizeResponse,
 ): PseudonymizeResponse {
@@ -34,10 +94,12 @@ export function normalizePseudonymizeResponse(
     text = text.replace(bareRegex, bracketed);
   }
 
+  const rebalanced = rebalanceBrackets(text, normalizedMapping);
+
   return {
     ...response,
-    pseudonymized_text: text,
-    mapping: normalizedMapping,
+    pseudonymized_text: rebalanced.text,
+    mapping: rebalanced.mapping,
   };
 }