In 2000, his research paper "When an Event is Not an Event" uncovered the rampant insider trading on Mexican stock markets. This led to many questions about the value and the enforceability of insider trading laws. Later, in "The World Price of Insider Trading" he discovered the fact that insider trading laws in themselves are not effective - they only start being effective once there is credible enforcement. Additionally he could "put a price on honesty", i.e. quantify the advantage of insider trading laws and the price of "window dressing" of company earnings.
As of December 2008, he is an Associate Professor at the Kelley School of Business at IU. Before his time at Indiana University, Bhattacharya has been teaching at Columbia University and the University of Iowa. He has been a visiting professor at Duke University and MIT. He received his undergraduate degree in mechanical engineering from IIT Kanpur in 1980, an MBA from IIM Ahmedabad in 1982, and a Ph.D. degree from Columbia University in 1990. He held the title of James R. Hodge Eminent Scholar in Finance at IU from 2004 to 2006.
- "To Believe or Not to Believe" (with Murgie Krishnan), Journal of Financial Markets, 1999, vol 2, 69-98
- "When an Event is Not an Event: The Curious Case of an Emerging Market" (with Hazem Daouk, Brian Jorgenson and Carl-Heinrich Kehr), Journal of Financial Economics, 2000, vol 55, 69-101
- "The World Price of Insider Trading" (with Hazem Daouk), Journal of Finance, 2002, vol 57, 75-108
- "The World Price of Earnings Opacity," (with Hazem Daouk and Michael Welker), The Accounting Review, 2003, vol 78, 641-678
- "Is CEO Certification Credible?" (with Peter Groznik and Bruce Haslem), Regulation, 2003, Vol 26, 8-10, Cato Institute, Washington, D.C.
- "Penny Wise, Dollar Foolish: Buy-Sell Imbalances On and Around Round Numbers" (with Craig Holden and Stacey Jacobsen), Management Science, 2012, Vol 15, 413-431.
- Margaret Popper, "Economic Trends", Businessweek Online, July 22 2002 
- "Worthless promises? - Did it pay to make American CEOs certify their accounts?", The Economist, 28 September 2002