diff --git a/src/sssom/obo.epm.json b/src/sssom/obo.epm.json
index f9fc8149..67983ff8 100644
--- a/src/sssom/obo.epm.json
+++ b/src/sssom/obo.epm.json
@@ -25422,10 +25422,10 @@
     },
     {
         "prefix": "vann",
-        "uri_prefix": "https://vocab.org/vann/",
+        "uri_prefix": "https://vocab.org/vann/#",
         "uri_prefix_synonyms": [
             "http://bioregistry.io/vann:",
-            "http://vocab.org/vann/",
+            "http://vocab.org/vann/#",
             "https://bioregistry.io/vann:"
         ]
     },