diff --git a/python/nav/bin/update_ouis.py b/python/nav/bin/update_ouis.py
index f31cc5a0dd..8878ccd612 100755
--- a/python/nav/bin/update_ouis.py
+++ b/python/nav/bin/update_ouis.py
@@ -17,7 +17,7 @@
 
 import logging
 
-from typing import List, Iterable
+from typing import List, Iterable, Generator
 
 import requests
 from requests.exceptions import RequestException
@@ -53,16 +53,14 @@ def _download_oui_file(url: str) -> str:
     return response.text
 
 
-def _parse_ouis(oui_data: str) -> List[OUI]:
+def _parse_ouis(oui_data: str) -> Generator[OUI, None, None]:
     """Returns lists of tuples containing OUI and vendor name for
     each vendor
     """
-    oui_list = []
     for line in oui_data.split('\n'):
         if "(hex)" not in line:
             continue
-        oui_list.append(_parse_line(line))
-    return oui_list
+        yield _parse_line(line)
 
 
 def _parse_line(line: str) -> OUI: