diff --git a/src/newgrf_config.cpp b/src/newgrf_config.cpp
index 5bc4fb5182..8985f4c181 100644
--- a/src/newgrf_config.cpp
+++ b/src/newgrf_config.cpp
@@ -73,7 +73,6 @@ GRFConfig::GRFConfig(const GRFConfig &config) :
 void GRFConfig::CopyParams(const GRFConfig &src)
 {
 	this->num_params = src.num_params;
-	this->num_valid_params = src.num_valid_params;
 	this->param = src.param;
 }