diff --git a/lib/server/search.ts b/lib/server/search.ts
index f6d198d..fc884f1 100644
--- a/lib/server/search.ts
+++ b/lib/server/search.ts
@@ -17,7 +17,7 @@ import {
   listResearchJournalEntries,
   listResearchJournalEntriesForUser
 } from '@/lib/server/repos/research-journal';
-import { normalizeTicker } from '@/lib/server/utils';
+import { normalizeTickerOrNull } from '@/lib/server/utils';
 
 type SearchDocumentScope = 'global' | 'user';
 type SearchDocumentSourceKind = 'filing_document' | 'filing_brief' | 'research_note';
@@ -1201,7 +1201,7 @@ export async function searchKnowledgeBase(input: SearchInput) {
   }
 
   const limit = clampLimit(input.limit);
-  const normalizedTicker = normalizeTicker(input.ticker);
+  const normalizedTicker = normalizeTickerOrNull(input.ticker);
   const includedSources = normalizeSearchSources(input.sources);
   const client = getSqliteClient();
   const [queryEmbedding] = await runAiEmbeddings([normalizedQuery]);