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There are dozens (if not hundreds) of companies providing merchant services on the Internet. It makes no difference to inLeague which merchant service provider you use; however, they must support Authorize.net OR FirstData E4 as a payment gateway. Note that there are several 'FirstData' payment gateways; E4, also called 'PayEezy,' is the only one supported by inLeague.
Leagues using a merchant services provider other than Flagship are responsible for their own PCI compliance surveys and scans.
Special Note on Refund Windows: Please be aware that, while inLeague supports Authorize.net as a gateway, they will not refund any transaction past 120 days. If you need to refund any payment after 120 days, please ensure that Flagship uses FirstData's E4 product as your payment gateway.
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