 ALLENTOWN, Pa. LAS VEGAS--BUSINESS WIRE--- FOUR--Shift4 Payments NYSE: FOUR, the leader in integrated payment processing solutions, has posted its second quarter 2021 financial results as part of its 2Q 2021 shareholder letter under the Financials section of its Investor Relations website at The Companys shareholder letter can also be viewed here Shift4 Payments 2Q 2021 Shareholder Letter Management will host a conference call today, August 5 