More than a dozen US-based employees of Taiwanese chipmaking giant TSMC have sued the company for apparent discrimination against non-Asian workers, according to a recent lawsuit.

The suit alleges that the world's largest contract manufacturer of chips -- used in everything from Apple iPhones to Nvidia's AI hardware -- unfairly favors Asian staff in terms of hiring, firing and working standards.

Initially filed in August, the suit was refiled last week as a class action case with 13 plaintiffs named.

Taiwan Semiconductor Manufacturing Company declined to comment on the litigation but said in a statement on Thursday that it "believes strongly in the value of a diverse workforce."

The company is at the forefront of a generative AI revolution, churning out the world's most advanced microchips needed to power products made by Silicon Valley.

It has secured billions of dollars in US funding and has agreed to operate three factories in Arizona.

The suit alleges that TSMC routinely subjects those who don't hail from Taiwan or China to a "hostile work environment where verbal abuse, gaslighting, isolation, and humiliation is common, and oftentimes leads to the constructive discharge of these employees."

The 13 plaintiffs -- whose backgrounds include the United States, Mexico, Nigeria, Europe and Korea -- were seeking damages to redress TSMC's apparent discrimination practices.

The lawsuit was first filed in August by TSMC recruitment manager Deborah Howington, alleging bias towards Asians, and particularly Taiwanese citizens, in decisions on hiring and termination of employment.

It claims that non-Asian workers are "frequently excluded from business discussions, as conversations are often conducted in Mandarin, and business documents are routinely written in Mandarin."

TSMC said in a statement that "we hire and promote without regard to gender, religion, race, nationality, or political affiliation because we respect differences, and believe that equal employment opportunities strengthen our competitiveness."