diff --git a/include/hardware/hw_auth_token.h b/include/hardware/hw_auth_token.h
index f471d1a..d84ea48 100644
--- a/include/hardware/hw_auth_token.h
+++ b/include/hardware/hw_auth_token.h
@@ -23,7 +23,7 @@
 extern "C" {
 #endif  // __cplusplus
 
-const uint8_t HW_AUTH_TOKEN_VERSION = 0;
+static const uint8_t HW_AUTH_TOKEN_VERSION = 0;
 
 typedef enum {
     HW_AUTH_NONE = 0,