diff --git a/EIPS/eip-649.md b/EIPS/eip-649.md
index b4e72a0e..ebdc9969 100644
--- a/EIPS/eip-649.md
+++ b/EIPS/eip-649.md
@@ -60,8 +60,15 @@ The following clients implemented EIP-649:
 - Geth [#15028](https://github.com/ethereum/go-ethereum/pull/15028)
 - Parity [#5855](https://github.com/paritytech/parity/pull/5855)
 - EthereumJ [#927](https://github.com/ethereum/ethereumj/pull/927)
+- Cpp-Ethereum [#4050](https://github.com/ethereum/cpp-ethereum/issues/4050)
+- PyEthereum [#383](https://github.com/ethereum/pyethereum/pull/383)
 
 The Yellow Paper implements EIP-649 in [#333](https://github.com/ethereum/yellowpaper/pull/333).
 
+Other notable implementations:
+
+- Eth-Isabelle [#459](https://github.com/pirapira/eth-isabelle/issues/459)
+- Py-EVM [#123](https://github.com/pipermerriam/py-evm/pull/123)
+
 ## Copyright
 Copyright and related rights waived via [CC0](https://creativecommons.org/publicdomain/zero/1.0/).