There are different reasons why one may write a business guarantee letter. When an investor is writing a call option for underlying stock that does not reside in his or her brokerage account, then they will write a business guarantee letter. Banks will also write business guarantee letters for clients who own a certain security. This letter will state that the bank is guaranteeing delivery of
. that security to the client. To read a sample business guarantee letter, visit https://secure.allwest.net/docs/bus_letter_of_guarantee.pdf.