Macerich Co. on Thursday priced a larger-than-initially announced offering of 30 million shares at $41 per share, which now could gross the shopping mall owner at least $1.23 billion.

The Santa Monica real estate investment trust said it intends to use net proceeds to pay off debt and for general corporate purposes. Macerich currently has 96.5 million shares outstanding.

Deutsche Bank Securities Inc. and J.P. Morgan Securities Inc. are acting as joint book-running managers and underwriters for the offering. The REIT plans to grant underwriters a 30-day option to purchase up to 4.5 million additional shares to cover over-allotments.

The offering, first announced Wednesday, is expected to close on April 20, the company said. The company initially said it planned to sell 18.5 million shares, with an additional 2.7 million share option for over-allotments.

In a separate release Wednesday, Macerich revised its fiscal 2010 guidance. It now expects to report funds from operations of between $2.70 and $2.90 per share, compared to the previous guidance of $2.90 to $3.10 per share. FFO is a performance measure used by REITs that removes the profit-reducing effect of depreciation from net income.

Shares on Thursday closed down $2.83, or 6.5 percent, to $40.90 on the New York Stock Exchange.