Infosys, the company founded by Rishi Sunak’s father-in-law NR Narayana Murthy, is in a multimillion-pound dispute with the UK tax authorities. HMRC and the Indian IT services firm, in which the prime minister’s wife, Akshata Murty, holds a stake of close to 1%, disagree over a corporation tax bill of about £20m, according to the company’s annual report. The dispute, first revealed by the Times, is one of a clutch of tax issues the company has in a range of jurisdictions, including Australia. Large tax disagreements that could affect a company’s operations or profits often have to be disclosed to shareholders and regulators. Infosys is publicly listed in India and New York. A spokesperson for Infosys told the Guardian: “Infosys provides details of certain ongoing disputes with various regulatory authorities, including this specific tax matter with HMRC. The company has filed an appeal against a tax assessment in the UK and has obtained a stay on the payment of the tax demand from HMRC.” Narayana Murthy is no longer involved in the direct management of Infosys, after resigning from a senior role in 2014. Akshata Murty is also not involved in running the company, but retains shares worth almost £700m, which form a large share of the Sunaks’ family wealth. These have earned her tens of millions of pounds in dividends in recent years. The tax dispute comes at a sensitive time for the prime minister, who last week sacked the Tory party chair, Nadhim Zahawi, because of a breach of the ministerial code tied to a tax penalty. Sunak is still facing scrutiny over his handling of the affair. In April last year it was also revealed that Murty saved millions of pounds while living in No 11 by using non-dom status to minimise her tax bill. The tax break, which costs thousands of pounds to maintain, means that a person can be a UK resident but only pay tax on the British – rather than worldwide – income. Murty resigned her non-dom status for income tax purposes shortly afterward. It is possible to retain the benefits of non-dom status even after it has expired or been resigned via an offshore trust.