diff --git a/include/ecrt.h b/include/ecrt.h
index a6098f2f..63ce3fa2 100644
--- a/include/ecrt.h
+++ b/include/ecrt.h
@@ -2458,7 +2458,7 @@ EC_PUBLIC_API uint8_t *ecrt_reg_request_data(
  *
  * \ingroup ApplicationInterfaceRT
  */
-ec_request_state_t ecrt_reg_request_state(
+EC_PUBLIC_API ec_request_state_t ecrt_reg_request_state(
         const ec_reg_request_t *req /**< Register request. */
     );