diff --git a/request_handler.go b/request_handler.go
index c47be7e..d68eca8 100644
--- a/request_handler.go
+++ b/request_handler.go
@@ -15,6 +15,7 @@ type CuitError struct {
 }
 
 const NO_SEARCH_ARG = "Sin argumento de búsqueda"
+const INVALID_CUIT = "CUIT inválido"
 
 func RequestHandler(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "application/json")
@@ -45,6 +46,8 @@ func RequestHandler(w http.ResponseWriter, r *http.Request) {
 				} else {
 					errorResponse.Error = err.Error()
 				}
+			} else {
+				errorResponse.Error = INVALID_CUIT
 			}
 		}
 	}