The Securities and Exchange Commission (SEC) said Dharmadasa, the head of Sri Lanka Cricket, and eight others had boosted the share price of Nawaloka Hospitals by furious buying and selling designed to attract investor interest.
The nine had committed "acts to create a false and misleading appearance of an active share market and the offences of aiding and abetting and conspiracy in the commission of these offences," the securities commission said in a statement.
If found guilty, the nine could either face a five-year jail sentence, a 10 million rupee ($100,000) fine or both, the securities commission said.
Dharmadasa's family controls the Nawaloka Group, whose investments include construction, plastic, timber, trading and heavy machinery. The family took the hospital unit public in 2004.
Nawaloka, Sri Lanka's second-largest private hospital, raised 300 million rupees by selling a 30 percent stake to the public aimed at paying debt and adding a five-storey wing.