diff --git a/app/static/js/releve-but.js b/app/static/js/releve-but.js
index 1e8a4a33..b0ad3443 100644
--- a/app/static/js/releve-but.js
+++ b/app/static/js/releve-but.js
@@ -220,6 +220,9 @@ class releveBUT extends HTMLElement {
 				<div>Min. promo. :</div><div>${data.semestre.notes.min}</div>
 			</div>
 			${(() => {
+				if (data.semestre.rang.groupes == null) {
+					return "";
+				}
 				if (Object.keys(data.semestre.rang.groupes).length == 0) {
 					return "";
 				}