diff --git a/src/hooks/useValidation/validators.js b/src/hooks/useValidation/validators.js
index a74327d1..68c3edb0 100644
--- a/src/hooks/useValidation/validators.js
+++ b/src/hooks/useValidation/validators.js
@@ -483,7 +483,7 @@ export const validateLccnDuplication = async ({
     };
 
     if (marcType === MARC_TYPES.BIB) {
-      searchParams.query += ' and (staffSuppress=="false" or discoverySuppress=="false")';
+      searchParams.query += ' not (staffSuppress=="true" and discoverySuppress=="true")';
     }
 
     const requests = {
diff --git a/src/hooks/useValidation/validators.test.js b/src/hooks/useValidation/validators.test.js
index aa53825b..b2df1bfb 100644
--- a/src/hooks/useValidation/validators.test.js
+++ b/src/hooks/useValidation/validators.test.js
@@ -805,7 +805,7 @@ describe('validators', () => {
 
       expect(ky.get).toHaveBeenCalledWith('search/instances', {
         searchParams: expect.objectContaining({
-          query: expect.stringContaining(' and (staffSuppress=="false" or discoverySuppress=="false")'),
+          query: expect.stringContaining(' not (staffSuppress=="true" and discoverySuppress=="true")'),
         }),
       });
     });