In October or November of each year, the IRS sends Grubhub a CP2100 notice stating that certain 1099-Ks provided for the prior year had taxpayer name and number combinations that did not match their records.
We are required to send the listed taxpayers B-Notice letters to obtain a W9 and immediately start withholding 28% of all funds due. This withholding occurs until we receive the updated W9, and the withholding is paid to the IRS each month. It is then reflected in Box 4 of the 1099-K.
Before starting this withholding, we send several notifications via direct mail, fax, email, and phone.