An ancillary document that amends or supplements the primary document is known as a rider. A rider may create additional terms to a contract. For example, in Blackburn Food Corp. v. Ardi, Inc., the New York Supreme Court Appellate Division analyzed a lease which contained a rider giving tenants an option to purchase the premises. In the legislative context, the U.S. Senate glossary describes rider as an “[i]nformal term for a nongermane amendment to a bill or an amendment to an appropriation bill that changes the permanent law governing a program funded by the bill.” That is, a rider is an amendment to a law or new law that is attached onto a bill, but is not directly related to that bill.
[Last updated in April of 2021 by the Wex Definitions Team]