[7] The Supreme Court first recognized the doctrine of contributory infringement in 1924, in William R. Warner & Co. v. Eli Lilly & Co.[8][9] In this case, the salesmen for the defendant, a manufacturer, suggested to retail dealers that defendant's product could be imperceptibly substituted for the plaintiff's product.

"[8] The plaintiff, Ives Laboratories, Inc., owned a patent on the drug cyclendelate, which it distributed in colored blue and blue-red capsules and marketed under the name Cyclospasmol.

[10] After the patent expired in 1972, the defendant, Inwood Laboratories, Inc., and other manufacturers began to make and distribute generic versions of the drug using identically colored capsules.

[1] Ives sued several manufacturers and wholesalers under § 32 of the Lanham Act, alleging that some pharmacists were distributing generic versions of cyclendelate and mislabeling them as Cyclospasmol.

[18] Inwood involved a manufacturer or distributor, but it left open whether its test of contributory liability applied beyond this context.

[19] Since Inwood, courts have extended the application of contributory infringement to other areas, including flea markets,[19][20][21] franchises,[22] and service providers[23][6]