Anti-corruption activists last week accused DLF of improper land deals with Robert Vadra in return for government favours.
On Monday DLF's purchase in 2008 of 3.5 acres (1.4 hectares) of land from Vadra for $10.9 million was cancelled by an official in the northern state of Haryana, who said land transfer guidelines were violated.
Shares of DLF, which has denied any malpractice, fell by as much as 4.85 percent or 10.55 rupees during Tuesday trading to a low of 206.7 rupees. They closed down 4.26 percent at 208 rupees.
DLF declined to respond Tuesday but last week said that it "neither sought nor enjoyed any special favours" and that all its dealings with Vadra were conducted "to the highest ethical standards".
Vadra, a wealthy businessman married to Sonia Gandhi's daughter Priyanka, has also dismissed the charges as baseless.
Italian-born Sonia Gandhi is seen as India's most influential politician and the family is fiercely guarded by ruling Congress party members who have rallied to Vadra's defence.