function _privateSaleTransferFromOwner(address _to, uint256 _amount)
        private returns (bool)
    {
        uint256 newTotalPrivateSaleAmount = totalPrivateSalesReleased.add(_amount);
        
        require(newTotalPrivateSaleAmount <= PRIVATE_SALE_AMOUNT.mul(10 ** uint256(decimals)));

        bool result = super.transferFrom(owner, _to, _amount);
        privateSalesReleased[msg.sender] = privateSalesReleased[msg.sender].add(_amount);
        totalPrivateSalesReleased = newTotalPrivateSaleAmount;
        return result;
    }