Confirmed with Gusto. They send data to WorkNumber.
"...for the purpose of automating employment and income verifications. This feature helps streamline the process for employees who may need to provide proof of employment or income for loans, credit, or public aid."
"...for the purpose of automating employment and income verifications. This feature helps streamline the process for employees who may need to provide proof of employment or income for loans, credit, or public aid."