There are times when a church will need a copy of their 501C3 letter, which is from the IRS and under the blanket of the Presbyterian Church (U.S.A.). (TechSoup is an example of a vendor that would need a 501c3 letter if someone is creating an account with them.)
There is a link that a church or even a presbytery can use to get the letter themselves. The link is available by clicking here.