diff --git a/ecdsa.go b/ecdsa.go
new file mode 100644
index 0000000..9e7055f
--- /dev/null
+++ b/ecdsa.go
@@ -0,0 +1,9 @@
+package varsig
+
+// Stub
+const (
+	SignAlgorithmECDSASecp256k1 SignAlgorithm = 0xe7
+	SignAlgorithmECDSAP256      SignAlgorithm = 0x1200
+	SignAlgorithmECDSAP384      SignAlgorithm = 0x1201
+	SignAlgorithmECDSAP521      SignAlgorithm = 0x1202
+)