US data analytics firm Palantir, which has drawn fire over its law enforcement and national security work, made a low-key debut on Wednesday on Wall Street at a hefty valuation of more than $20 billion.

Palantir, whose name comes from the mystical, all-powerful seeing stone in “Lord of the Rings”, opted for a direct listing which raises no new cash but allows its shares to be traded publicly.

The debut came without fanfare, as the trade opened with no splashy bell-ringing event for Palantir, using the symbol PLTR, at the New York Stock Exchange.

The shares opened in early afternoon at $10, representing a market value of some $21.7 billion – close to its valuation by private investors.

After some swings higher, Palantir ended at $9.50, making its value slightly above $20 billion.

The company, created in Silicon Valley and recently relocated to Denver, has argued that its tech platform helps catch terrorists and keep people safe.

But some activists argue that Palantir’s technology – which scoops up financial records, social media posts, call records and internet records – enables unprecedented opportunities for mass surveillance with little oversight on privacy and fundamental rights.

Amnesty International said in a report this week that Palantir’s contracts with US authorities to target asylum seekers “raise serious questions about the company’s actions to uphold its responsibility to respect human rights”.

The report said Palantir “has a responsibility to avoid causing or contributing to human rights abuses, and to address human rights impacts in which they are involved” under UN guidelines.

Responding to the Amnesty report, Palantir said it has no contracts with US Customs and Border Protection and claimed it was the subject of “misreporting and conflation” of its activities.

In its prospectus, Palantir said it offers software to defence and intelligence agencies “whose missions are to keep us safe”, while adding that it steers clear of data tracking used by other large technology firms.

“Our software is used to target terrorists and to keep soldiers safe,” the company said. “We have chosen sides, and we know that our partners value our commitment.”