SEC Proposes Crackdown on Executives’ Well-Timed Stock Sales (1)

Corporate chieftains have long been suspected of skirting rules that are meant to prevent top executives from trading on inside information. Now, the Securities and Exchange Commission is cracking down.

The regulator is addressing a controversial question: When should corporate insiders, who may have access to material non-public information, be allowed to sell stock? Currently, executives can set up sales just days before dumping shares, which Senator Elizabeth Warren and other lawmakers say enables them to front run corporate announcements that can move share prices.

In response, the SEC on Wednesday unanimously proposed new rules that would force company insiders ...