diff --git a/ethcore/src/ethereum/mod.rs b/ethcore/src/ethereum/mod.rs
index 75c321ebe..09b272cb3 100644
--- a/ethcore/src/ethereum/mod.rs
+++ b/ethcore/src/ethereum/mod.rs
@@ -31,7 +31,7 @@ use machine::EthereumMachine;
 use super::spec::*;
 
 /// Most recent fork block that we support on Mainnet.
-pub const FORK_SUPPORTED_FOUNDATION: u64 = 2675000;
+pub const FORK_SUPPORTED_FOUNDATION: u64 = 4370000;
 
 /// Most recent fork block that we support on Ropsten.
 pub const FORK_SUPPORTED_ROPSTEN: u64 = 10;