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diff --git a/packages/contracts/contracts_old/UnlimitedAllowanceToken/v1.sol b/packages/contracts/contracts_old/UnlimitedAllowanceToken/v1.sol
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+/*
+
+ Copyright 2017 ZeroEx Intl.
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+
+*/
+
+pragma solidity ^0.4.11;
+
+import "../../packages/StandardToken/StandardToken.sol";
+
+contract UnlimitedAllowanceToken is StandardToken {
+
+ uint constant MAX_UINT = 2**256 - 1;
+
+ /// @dev ERC20 transferFrom, modified such that an allowance of MAX_UINT represents an unlimited allowance.
+ /// @param _from Address to transfer from.
+ /// @param _to Address to transfer to.
+ /// @param _value Amount to transfer.
+ /// @return Success of transfer.
+ function transferFrom(address _from, address _to, uint _value)
+ public
+ returns (bool)
+ {
+ uint allowance = allowed[_from][msg.sender];
+ if (balances[_from] >= _value
+ && allowance >= _value
+ && balances[_to] + _value >= balances[_to]
+ ) {
+ balances[_to] += _value;
+ balances[_from] -= _value;
+ if (allowance < MAX_UINT) {
+ allowed[_from][msg.sender] -= _value;
+ }
+ Transfer(_from, _to, _value);
+ return true;
+ } else {
+ return false;
+ }
+ }
+}