Just days after Equifax Inc. discovered it had been hacked, three executives sold off $1.8 million worth of shares, a move that would avoid the price plummet that followed the credit bureau’s public disclosure of one of the largest data breaches in U.S. history.

Equifax has maintained the executives were unaware of the breach, which the company said it learned about on July 29, when they made those trades on Aug. 1. Still, published reports about the stock sales raise “fundamental questions,” two partners at the law firm Dorsey & Whitney said in an article published Friday at the Harvard Law School Forum on Corporate Governance and Financial Regulation.