diff --git a/app/models/security/importer.rb b/app/models/security/importer.rb
index ed515067..4146fea2 100644
--- a/app/models/security/importer.rb
+++ b/app/models/security/importer.rb
@@ -21,6 +21,21 @@ class Security::Importer
       .compact
       .uniq { |security| [ security[:ticker], security[:exchange_mic] ] }
 
+    # First update any existing securities that only have a ticker
+    Security.where(exchange_mic: nil)
+      .where(ticker: securities_to_create.map { |s| s[:ticker] })
+      .update_all(
+        securities_to_create.map do |security|
+          {
+            name: security[:name],
+            country_code: security[:country_code],
+            exchange_mic: security[:exchange_mic],
+            exchange_acronym: security[:exchange_acronym]
+          }
+        end.first
+      )
+
+    # Then create/update any remaining securities
     Security.upsert_all(
       securities_to_create,
       unique_by: [ :ticker, :exchange_mic ],