diff --git a/params/config.go b/params/config.go
index 609e86f9fd..197ed56f8a 100644
--- a/params/config.go
+++ b/params/config.go
@@ -1385,10 +1385,6 @@ type Rules struct {
 
 // Rules ensures c's ChainID is not nil.
 func (c *ChainConfig) Rules(num *big.Int, isMerge bool, timestamp uint64) Rules {
-	chainID := c.ChainID
-	if chainID == nil {
-		chainID = new(big.Int)
-	}
 	// disallow setting Merge out of order
 	isMerge = isMerge && c.IsLondon(num)
 	isVerkle := isMerge && c.IsVerkle(num, timestamp)