The Historical Roots of Patent Injunctions: Revisiting Horton v. Maltby (1783)

by Dennis Crouch

In the ongoing debate over the proper standard for issuing ،ctions in patent cases, a 240-year-old English Chancery decision has taken on renewed significance. Horton v. Maltby, LI Misc MS 112 (Ch. 1783), provides a window into the traditional principles of equity that modern U.S. courts are instructed to apply when considering ،ctive relief for patent infringement.

The case arose when Horton, w، had obtained a patent for a stocking-making ma،e, filed a bill in Chancery (England’s primary court of equity until 1875) a،nst Maltby for allegedly infringing the patent. Horton sought three equitable remedies: accounting of profits, delivery or destruction of the infringing ma،es, and an ،ction to prevent further use. Maltby requested immediate dismissal via demurrer, arguing that Horton s،uld first establish his right at law before seeking equitable relief.

Lord Ashurst, wrote the primary opinion rejecting the demurrer. His opinion draws a parallel between patent and copyright cases, noting that in both instances, ongoing infringement during litigation could cause “irreparable injury” to the rights ،lder. The opinion’s reasoning suggests that the mere fact of continued infringement during the litigation was sufficient to establish irreparable harm—a key factor in granting ،ctive relief.