Sun Pharmaceutical Industries plunged to its lowest point in almost six years after a media report that a new whistle-blower complaint alleging corporate governance lapses has been sent to India\u2019s market regulator. Shares of the nation\u2019s largest drugmaker slipped 8.4% to close at Rs 390.75 a share \u2014 the lowest level since March 2013. Sun Pharma was the day\u2019s worst performer on S&P BSE Sensex, data compiled by Bloomberg shows. A 172-page complaint sent to the Securities and Exchange Board of India (Sebi) \u2014 the capital market regulator \u2014 alleges one of the drugmaker\u2019s distributors, which has been declared as a related party, did `5,800 crore worth of transactions with a realty firm that is controlled by a director on Sun Pharma\u2019s board, according to a Moneylife report. Moneylife\u2019s offer to show these whistle-blower documents only \u201cto a set of selective investors does put other investors including retail investors in a disadvantageous position\u201d, Sun Pharma said in a letter to the market regulator on Friday. \u201cThere is a great asymmetry in the information circulating between analysts, investors and media leading to intense speculation.\u201d The latest news report about a fresh whistle-blower complaint has increased investor scrutiny on the drugmaker that\u2019s controlled by its billionaire founder and largest shareholder, Dilip Shanghvi. The complaints around corporate governance lapses threaten to overshadow the pharmaceutical company\u2019s progress winning new product approvals in the US. The drugmaker \u201chas been facing issues on corporate governance since the last few months\u201d and had briefed foreign institutional investors in December on this issue, said Sameer Kalra, president at Target Investing in Mumbai. Sun Pharma requested the market regulator to examine \u201cthe role of some media houses and other stakeholders\u201d in a \u201cmala fide campaign\u201d that has resulted in the stock\u2019s plunge. Sebi spokesman N Hariharan didn\u2019t respond to calls and text messages by Bloomberg seeking comment. Also read:\u00a0India may miss disinvestment target once again in FY19; fiscal deficit set to overshoot limit A November report by the Press Trust of India said Sebi is likely to reopen an insider trading case against Sun Pharma to probe alleged lapses by some of its promoters and other entities in raising funds oversees. This investigation was prompted by an earlier whistle-blower complaint, the PTI report had said.