We have things like our "Verified Sender" list, which includes companies like:
Fedex, DHL, UPS, PayPal, Amazon, DocuSign, eFax, RingCentral, HSBC Bank, BankofAmerica, Wells Fargo, Sam's Club, CostCo, USPS, CitiBank, Chase Bank, ADP
(and many many others)
When they send you a mail message, we mark it with a Green Checkmark, meaning it is safe to open.
Messages that pretend to be from these same senders, but are fakes, are tagged with our "Possible Phishing" warning.
Read more about Verified Senders