(FORTUNE Magazine) – Any CEOs still wondering if they need to pay attention to disgruntled shareholders pestering their board should consider the fate of Kmart CEO Joseph Antonini. After ignoring investors for years, his directors finally lopped off his title of chairman. CEOs who dither inevitably find their companies on the list of activists' least-loved stocks. Says Patrick McGurn, a director at the Investor Responsibility Research Center: "If you stay on that radar screen for too long, it's time to start rewriting your resume."

This proxy season should be busy for four companies targeted by activists. Even ITT and Baxter International, companies that some feel are coming around, face the Kmart fix. Shareholders of both are asking that the CEO and chairman jobs be split. While ITT's Rand Araskog has delivered an annual rate of return of 11.5% over the past five years, the International Brotherhood of Teamsters' pension funds think someone else should be approving moves like Araskog's acquisition of Caesars World. Meanwhile, the New York City Employees' Retirement System wants Baxter to separate the titles of CEO and chairman. Vernon Loucks Jr. is trying to breathe life into the ailing medical supplier, hit hard by health care cost cutting.

USAir's rate of return to investors has plummeted 33.7% a year since 1989, and the company lost $685 million last year. While some analysts still believe CEO Seth Schofield is a good captain, every institutional activist Fortune spoke to thought he faces stormy weather ahead.

United States Shoe is another underperformer. CEO Bannus Hudson may sell the namesake shoe business, retaining women's clothing and LensCrafters eyewear stores. But the stock is among the 50 worst in the portfolio of the California Public Employees' Retirement System. Calpers' proposal to destagger the board passed one hurdle last year and may be implemented in May. Says Calpers' general counsel Richard Koppes: "If you can get boards overseeing and challenging management early on, then you shouldn't have disruptive firings."

- Erick Schonfeld