diff --git a/bip-0138/test_vectors/encryption_secret.json b/bip-0138/test_vectors/encryption_secret.json
index c1afb023..b06d66b5 100644
--- a/bip-0138/test_vectors/encryption_secret.json
+++ b/bip-0138/test_vectors/encryption_secret.json
@@ -85,5 +85,16 @@
     "individual_secrets": [
       "c14d5bfeb7f9709e996c6696959107d4c57d367d2aee207d5361f116e3c4708b"
     ]
+  },
+  {
+    "description": "Keys sharing an x coordinate normalize to a single key",
+    "keys": [
+      "02e6642fd69bd211f93f7f1f36ca51a26a5290eb2dd1b0d8279a87bb0d480c8443",
+      "03e6642fd69bd211f93f7f1f36ca51a26a5290eb2dd1b0d8279a87bb0d480c8443"
+    ],
+    "decryption_secret": "9628546fe8fbf82fb10ff692d82953fa2db546275be9ce1b00134aff1a8bacdd",
+    "individual_secrets": [
+      "c14d5bfeb7f9709e996c6696959107d4c57d367d2aee207d5361f116e3c4708b"
+    ]
   }
 ]