(Corrects headline and first paragraph to say '3 years' not '2 years')

Nov 30 (Reuters) - A federal court in California on Wednesday allowed the Internal Revenue Service (IRS) to seek three years of information from blockchain firm Coinbase Inc about its American users, the U.S. Department of Justice (DOJ) said.

The court in Northern District of California authorized the IRS to serve a so-called "John Doe summons," used when the summoned person can't be identified, to Coinbase for U.S. taxpayers who conducted virtual currency transactions on its platform during 2013 to 2015.

"We look forward to opposing the DOJ's request in court after Coinbase is served with a subpoena," a spokesman for the San Francisco-based company said in an email to Reuters.

Coinbase remains concerned with its U.S. customers' privacy rights in the face of the government's request, he added.

(Reporting by Ismail Shakil and Sruthi Shankarin Bengaluru; Editing by Sandra Maler)