diff --git a/contracts/pools/erc20.sol b/contracts/pools/erc20.sol
index 48523a6..7fd0c9a 100644
--- a/contracts/pools/erc20.sol
+++ b/contracts/pools/erc20.sol
@@ -10,7 +10,6 @@ import { DSMath } from "../libs/safeMath.sol";
 
 interface IndexInterface {
   function master() external view returns (address);
-  function build(address _owner, uint accountVersion, address _origin) external returns (address _account);
 }
 
 interface RegistryInterface {
diff --git a/contracts/pools/eth.sol b/contracts/pools/eth.sol
index 58767c6..ba77eee 100644
--- a/contracts/pools/eth.sol
+++ b/contracts/pools/eth.sol
@@ -10,7 +10,6 @@ import { DSMath } from "../libs/safeMath.sol";
 
 interface IndexInterface {
   function master() external view returns (address);
-  function build(address _owner, uint accountVersion, address _origin) external returns (address _account);
 }
 
 interface RegistryInterface {