Activist investor Bill Ackman and the board of J.C. Penney Co. are disagreeing -- very publicly -- about who should head the struggling retailer.
Ackman and the department store chain exchanged a volley of letters and statements this week, squabbling over the search to replace interim Chief Executive Myron Ullman and whether Chairman Thomas Engibous should keep his job.
Ackman, who runs the Pershing Square Capital Management hedge fund and is a J.C. Penney director, kicked off the tussle Thursday. In a public letter first reported by CNBC, he urged J.C. Penney to quickly find a permanent resident for the chief executive post that Ullman has occupied since April.
It's not Ullman's first stint at the helm. He was chief executive at the Plano, Tex. retailer before being succeeded by Apple alum Ron Johnson in 2011, an appointment orchestrated by Ackman.
Less than two years and several consecutive quarters of double-digit sales declines later, Johnson was out and Ullman was taking back the reins.
But now Ackman wants a replacement for Ullman named in the next 30 to 45 days, according to his letter. If the board chooses an Ackman-approved candidate, he said Allen Questrom -- another former J.C. Penney chief executive -- would join the ranks as chairman.
The board didn't take well to Ackman's plea, according to a statement it released later Thursday.
Engibous wrote that the board "strongly disagrees" with Ackman "and is extremely disappointed" in the public nature of his letter.
"His latest actions are disruptive and counterproductive at an important stage in the Company's recovery," Engibous wrote.
In its statement, the board also backed Ullman with "overwhelming support," saying he has "led significant actions to correct the errors of previous management."
Still, Engibous wrote, the company kicked off its CEO search process "in earnest three weeks ago" and promised a "careful and deliberate" process.
Ackman lashed back on Friday, releasing a long missive to the board in which he called his first letter "admittedly an extraordinary step" but one that he considered "a last resort."
J.C. Penney's "very existence is at risk," he wrote, accusing "a small subset of the board" of "negotiating and speaking on behalf of the full board."
"In recent weeks, our board has ceased to function effectively," Ackman wrote.
He said that Ullman, without notifying the board, has blocked advisors from consulting J.C. Penney's financial data, made hiring and firing decisions and misled analysts on Wall Street.
"We are now flying blind," Ackman wrote.
The hedge fund manager also targeted Engibous, saying he failed to entertain discussions about the company's problems. Ackman even intimated that Engibous might be wrapped up in "outside business dealings" with Ullman, such as splitting a Gulfstream V aircraft.
In his Friday letter, Ackman said he has "lost confidence" in Engibous and recommended that he be replaced.
As the back-and-forth plays out, J.C. Penney stock is at its lowest point in more than a decade as it heads into the thick of the key back-to-school shopping season. On Friday, the stock fell nearly 7%, or 92 cents, to $12.74 a share in midday trading in New York.