Three of the nation's biggest contact lens makers last month sued Utah over the law, which bans price-fixing for lenses and could have wide-ranging implications for the industry.
They argue the law is unconstitutional and was written to benefit retailers like 1-800-Contacts.
On May 1, Attorney General Sean Reyes' campaign deposited a $5,000 check from 1-800-Contacts.
Reyes and his campaign say the donation has no bearing on work at the attorney general's office, and Reyes has a duty to defend the law.
Josh Kanter is board president of the progressive, good-government group Alliance for a Better Utah. He says the donation is a conflict of interest and Reyes should return it.