"III-3.6000 Retaliation or coercion. Individuals who exercise their rights under the ADA, or assist others in exercising their rights, are protected from retaliation. The prohibition against retaliation or coercion applies broadly to any individual or entity that seeks to prevent an individual from exercising his or her rights or to retaliate against him or her for having exercised those rights ... Any form of retaliation or coercion, including threats, intimidation, or interference, is prohibited if it is intended to interfere."
A more comprehensive resource is the Web Content Accessibility Guidelines developed by the Web Accessibility Initiative. These guidelines help designers make web pages as accessible as possible to the widest range of users, including users with disabilities. The Web Accessibility Initiative is a subgroup of the World Wide Web Consortium — the same organization that standardizes the programming language followed by all web developers.
Recent years have seen an uptick in federal lawsuits filed against businesses and governments, alleging that their website violates the ADA by being insufficiently accessible to people with disabilities. In 2017, there were at least 814 such lawsuits against organizations in a variety of industries, from banks and credit unions to restaurants and e-commerce websites. The defendants include small businesses as well as major corporations such as Nike, Burger King, and the Hershey Company.