Bill Ackman says he finds short-seller's Adani Group report 'highly credible' – and notes similarities to 'pyramid scheme' Herbalife

• Hindenburg Research accused India's Adani Group of "brazen stock manipulation" in report published this week.
• Pershing Square CEO Bill Ackman said he found the short-seller's report "highly credible and extremely well researched".

Bill Ackman has voiced his support for Hindenburg Research's report accusing the Indian conglomerate Adani Group of "brazen stock manipulation and accounting fraud".

Short-sellers Hindenburg accused the world's third-richest man Gautam Adani of "pulling the largest con in corporate history" in a report published Tuesday, which the research firm said revealed the findings of a two-year investigation. Adani Group had inflated its own valuation by manipulating the stock market and committing accounting fraud, the report had said.

"I found the Hindenburg report highly credible and extremely well researched," Pershing Square Capital Management CEO Ackman aid on Twitter late Thursday.

Adani has said it could explore legal action against Hindenburg, with CFO Jugeshinder Singh calling the activist investor's report "maliciously mischievous" and "unresearched".

It's since issued an 18-page presentation called "Myths of Short Seller" where it sought to double down on its fightback against Hindeburg's report.

"Adani Group's response speaks volumes," Ackman said. "Caveat emptor."

Ackman also compared Adani Group to Herbalife – the multi-level marketing company that Pershing Square unsuccessfully shorted between 2012 and 2017 in one of the billionaire investor's biggest-ever losses.

"Adani's response to Hindenburg Research is the same as Herbalife's response to our original 350-page presentation," he added. "Herbalife remains a pyramid scheme."

Ackman added that his funds don't have long or short positions in either Adani or Herbalife – and said readers should view the tweets as his judgment on Hindenburg's latest report rather than investment advice.

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