PayPal Express Checkout for Authorize.Net enables you to offer PayPal as a payment option to your customers by incorporating it within your existing AIM XML API implementation. PayPal Express Checkout is currently not enabled through the SIM or DPM APIs.
Note that PayPal Express Checkout is not supported by some resellers and is not offered in some countries. For more information, contact your reseller. PayPal Express Checkout does not support the full PayPal feature-set, including $0 authorizations. PayPal transactions are not subject to AFDS fraud filters, except the IP blacklist filter.