Indian tax authorities have asked IBM's Indian unit to pay 53.57 billion rupees ($866.20 million) in outstanding income tax on fiscal 2009 revenue, media reported on Saturday.
In an emailed statement, an IBM India spokeswoman confirmed the company had received a tax notice, but declined to comment on the amount of tax liability or the nature of the notice.
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India's Income Tax office issued the company a notice for under-reporting revenue for fiscal 2009 by the Indian unit, the Business Standard newspaper said, citing a tax official.
"IBM does not agree with the tax department's claims and will aggressively defend itself through the appropriate judicial process," the IBM India spokeswoman said.