California's legislature has become the first in the US to approve a bill banning caste discrimination.
Legislators said the measure would protect people of South Asian descent who allege unfair treatment.
The governor must now decide whether to sign the bill into law. Seattle became the first US city to ban caste discrimination in February.
The caste system in India dates back over 3,000 years and divides Hindu society into rigid hierarchical groups.
The measure, which passed on Tuesday by 31-5, was sponsored by Democratic state senator Aisha Wahab, who said it would add caste as a protected category in the state's anti-discrimination laws alongside gender, race, religion and disability.
"We shined a light on a long-hidden form of discrimination thousands of years old, invisible shackles on the wrist of millions of people," said Ms Wahab, who is the first Muslim and Afghan-American woman elected to the state legislature.
Five Republican state senators voted against the legislation, arguing that discrimination was already illegal under state law.
The office of Governor Gavin Newsom, a Democrat, said he would evaluate the bill when it reaches his desk.
Some Hindu groups argued the caste system is not a serious issue in North America.
The Hindu American Foundation (HAF) wrote on social media: "This divisive bill that still implicitly singles out/targets South Asians must be vetoed @GavinNewsom!"
Some Dalit (formerly untouchables) activists have dismissed those claims, saying they have experienced discrimination from people of a privileged caste.
In 2020, the technology company Cisco was sued by the state after two high-caste Indian managers allegedly discriminated against a Dalit engineer, paying him a lower salary.