diff --git a/packages/twenty-server/src/engine/api/rest/input-request-parsers/filter-parser-utils/__tests__/add-default-conjunction.util.spec.ts b/packages/twenty-server/src/engine/api/rest/input-request-parsers/filter-parser-utils/__tests__/add-default-conjunction.util.spec.ts
index e1a2c69af19..2a81670b97a 100644
--- a/packages/twenty-server/src/engine/api/rest/input-request-parsers/filter-parser-utils/__tests__/add-default-conjunction.util.spec.ts
+++ b/packages/twenty-server/src/engine/api/rest/input-request-parsers/filter-parser-utils/__tests__/add-default-conjunction.util.spec.ts
@@ -12,4 +12,38 @@ describe('addDefaultConjunctionIfMissing', () => {
       'and(field[eq]:1)',
     );
   });
+
+  it('should add default conjunction when bare filters are mixed with nested conjunctions', () => {
+    expect(
+      addDefaultConjunctionIfMissing(
+        "status[eq]:'TODO',and(title[ilike]:'%test%')",
+      ),
+    ).toEqual("and(status[eq]:'TODO',and(title[ilike]:'%test%'))");
+  });
+
+  it('should add default conjunction for multiple bare filters with nested or', () => {
+    expect(
+      addDefaultConjunctionIfMissing(
+        "field1[in]:['a','b'],or(field2[like]:'%x%')",
+      ),
+    ).toEqual("and(field1[in]:['a','b'],or(field2[like]:'%x%'))");
+  });
+
+  it('should not add default conjunction for or root conjunction', () => {
+    expect(
+      addDefaultConjunctionIfMissing('or(field[eq]:1,field[eq]:2)'),
+    ).toEqual('or(field[eq]:1,field[eq]:2)');
+  });
+
+  it('should not add default conjunction for not root conjunction', () => {
+    expect(addDefaultConjunctionIfMissing('not(field[eq]:1)')).toEqual(
+      'not(field[eq]:1)',
+    );
+  });
+
+  it('should add default conjunction for multiple bare filters', () => {
+    expect(
+      addDefaultConjunctionIfMissing('field1[eq]:1,field2[gte]:10'),
+    ).toEqual('and(field1[eq]:1,field2[gte]:10)');
+  });
 });
diff --git a/packages/twenty-server/src/engine/api/rest/input-request-parsers/filter-parser-utils/add-default-conjunction.util.ts b/packages/twenty-server/src/engine/api/rest/input-request-parsers/filter-parser-utils/add-default-conjunction.util.ts
index 8fde997cd91..aecf7e800c7 100644
--- a/packages/twenty-server/src/engine/api/rest/input-request-parsers/filter-parser-utils/add-default-conjunction.util.ts
+++ b/packages/twenty-server/src/engine/api/rest/input-request-parsers/filter-parser-utils/add-default-conjunction.util.ts
@@ -2,8 +2,12 @@ import { Conjunctions } from 'src/engine/api/rest/input-request-parsers/filter-p
 
 export const DEFAULT_CONJUNCTION = Conjunctions.and;
 
+const ROOT_CONJUNCTION_REGEX = new RegExp(
+  `^(${Object.values(Conjunctions).join('|')})\\((.+)\\)$`,
+);
+
 export const addDefaultConjunctionIfMissing = (filterQuery: string): string => {
-  if (!(filterQuery.includes('(') && filterQuery.includes(')'))) {
+  if (!ROOT_CONJUNCTION_REGEX.test(filterQuery)) {
     return `${DEFAULT_CONJUNCTION}(${filterQuery})`;
   }