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The apex court noted that with regard to assessment year 2018-19, it has been informed that the two petitioners had filed the ITR in terms of the orders of the high court and the assessment has also been completed.
"We therefore make it clear that for the assessment year 2019-20, the income tax return shall be filed in terms of the judgment passed by this court," the bench said on Monday.
"The special leave petition is disposed of in the above terms," the bench added.
This order means that individuals are required to mandatorily link their PAN with Aadhaar number for filing ITR.
The petitioners had earlier told the high court that "despite orders, and multiple attempts they have not been able to file their ITR, since there is no available option to opt-out of providing an Aadhaar or Aadhaar Enrolment number during e-filing, on the website".
Earlier in September last year, the apex court had declared the Centre's flagship Aadhaar scheme as constitutionally valid.
However, the apex court had struck down some of the Aadhaar provisions including its linking with bank accounts, mobile phones and school admissions.
A five-judge constitution bench had held that while Aadhaar would remain mandatory for filing of I-T returns and allotment of Permanent Account Number (PAN), it would not be mandatory to link Aadhaar to bank accounts and telecom service providers cannot seek its linking for mobile connections.
Aadhaar is a unique 12-digit identification number issued to individuals by the Unique Identification Authority of India after storing their biometrics data. The UIDAI uses iris and fingerprint scans to obtain biometric data from an applicant and store it in a database.
(With inputs from PTI)