BANGKOK, Nov 26 (Openly) - Ten years after it was introduced, India's national digital identity system is becoming ubiquitous in the country, even as large numbers of homeless and transgender people are excluded and many denied essential services, a study showed.

More than 1.2 billion Aadhaar IDs have been issued, according to government data. It is the world's largest biometric identity system, and the 12-digit ID is used for everything from school enrolments to tax filings.

But an estimated 102 million people do not have Aadhaar, including 30% of India's homeless population and more than a quarter of its third-gender citizens, said a report published late on Monday by Dalberg, a consulting firm. Those without Aadhaar include about 90% of residents in the northeastern state of Assam, where nearly 2 million people were left off a list of citizens published in August.

"The most marginalised populations are less likely to have Aadhaar and more likely to have errors in their Aadhaar information," said the report. The errors could "lead to denial of welfare services, and at times exclusion," it said.

A spokesman for the Unique Identification Authority of India (UIDAI), which oversees Aadhaar, did not respond to a request for comment. Read more via Openly