Additional data is any data that is appended to the affiliate's URL using a parameter name=value pair. The affiliate can use any name and value. LinkTrust takes the parameter name used by the affiliate and creates a token to match the parameter. The value of the parameter is placed into the token. This is called tokenizing the value. The token allows the affiliate to pass information through LinkTrust to the merchant and back to the affiliate. 

If an affiliate wants to send additional data to a merchant's landing page, the name of the beginning parameter must match the merchant's website form, so that the value is dynamically placed in the correct field.

For example, the merchant has a website form with fields for a consumer's first name, last name, and email address. The affiliate also has a website with a form that has already captured the consumer's first name, last name, and email address. The affiliate sends the consumer to the merchant's page along with the consumer's first name, last name, and email address. When the consumer lands on the merchant's page, those three fields are pre-populated on the merchant's page with the data sent by the affiliate. This happens because the affiliate appended the first name, last name, and email address parameters to the URL and passes the values to the merchant. This saves the consumer time having to re-enter the information twice.

Basically, by using additional data parameters and values, the affiliate can populate the merchant's website with the consumer information it has already collected.