Dozens of companies, including Alphabet Inc's Google, Microsoft Corp, CBS Corp and Viacom Inc urged a federal appeals court on Monday to rule that a law banning sex discrimination in the workplace offers protections to gay employees.

The brief submitted by 50 companies to the 2nd U.S. Circuit Court of Appeals in Manhattan marks the first time such a large group of businesses has backed arguments about employment discrimination that LGBT groups and the administration of former President Barack Obama have made for years.

The companies said bias against gay employees is widespread, with more than 40 percent of gay workers reporting harassment and other forms of discrimination in various studies. The lack of a federal law clearly prohibiting discrimination on the basis of sexual orientation has hindered recruitment in states that have not adopted their own, the companies said.

"Recognizing that our uniform federal law protects LGBT employees would benefit individual businesses, and the economy as a whole, by removing an artificial barrier to the recruitment, retention, and free flow of talent," wrote the companies' lawyers at Quinn Emanuel Urquhart & Sullivan. Read more via Reuters