Many laws specifically regulate the ways online ads are delivered. For example, online advertising delivered via email is more regulated than the same ad content delivered via banner ads. Among other restrictions, the U.S. CAN-SPAM Act of 2003 requires that any commercial email provide an opt-out mechanism. Similarly, mobile advertising is governed by the Telephone Consumer Protection Act of 1991 (TCPA), which (among other restrictions) requires user opt-in before sending advertising via text messaging.
The concept of affiliate marketing on the Internet was conceived of, put into practice and patented by William J. Tobin, the founder of PC Flowers & Gifts. Launched on the Prodigy Network in 1989, PC Flowers & Gifts remained on the service until 1996. By 1993, PC Flowers & Gifts generated sales in excess of $6 million per year on the Prodigy service. In 1998, PC Flowers and Gifts developed the business model of paying a commission on sales to the Prodigy Network.