The board of General Growth Properties—a longtime acquisition target for Indianapolis-based Simon Property Group Inc.—may reconsider a sale of the company two years after it spurned a Simon offer as the debt-laden Chicago-based mall owner restructured in bankruptcy court.

General Growth is interviewing investment banks this week, but it was not clear whether the intent of hiring a bank was to sell the company or as a defensive move, Reuters reported late Wednesday.

Activist investor Bill Ackman, who owns about 10 percent of General Growth's shares and is looking to cash in massive returns on his bet the company would survive its bankruptcy filing, has urged the mall owner to enter negotiations for a takeover by rival Simon.

Still, a deal is no sure bet, as General Growth's largest shareholder, Brookfield Asset Management Inc., may stand in the way.

General Growth, the No. 2 U.S. shopping-mall owner, exited bankruptcy protection in November 2010 following a takeover battle between Simon, its larger competitor, and an investor group that included Pershing Square and Brookfield.

A takeover by Simon may be difficult because Brookfield, which has a 42-percent stake, has said it doesn’t want to sell its shares, said John Sheehan, an analyst at Edward Jones in St. Louis.

Simon, in late 2011, discussed paying 0.1765 of a Simon share for each General Growth share, according to Ackman. That would would value General Growth at $27.87 a share, based on Simon’s Sept. 5 closing price.

That gives General Growth a higher per-share value than Simon’s proposed takeover from more than two years ago. Simon said in May 2010 that it offered $20 a share for its competitor, which was under bankruptcy protection at the time.