What would be the motivation for them to buy shares in the open market? Suresh for example has 1.7 million options. Do you really think he needs to add? I am pretty sure their investment advisors would tell them to diversify.

Any time they have made purchases it has had a very short term impact. That being said they were the first to invest in the debentures and had to get regulatory approval to go beyond 25% in the first tranche. That was primarily to show investors that it was a safe bet and it worked.