diff --git a/schemas/IBM.json b/schemas/IBM.json
index b4fa9b0..84f9cd4 100644
--- a/schemas/IBM.json
+++ b/schemas/IBM.json
@@ -85,6 +85,7 @@
                         "enum": [
                             "ibm,everest",
                             "ibm,rainier-2u",
+                            "ibm,rainier-1s4u",
                             "ibm,rainier-4u",
                             "ibm,rainier"
                         ]