GGP stock pricing held steady today after the retail REIT announced its shareholders had approved Brookfield Property Partners' offer to buy the second-largest U.S. mall owner. Brookfield's stock price dropped to $20.27/share.

The deal, first announced in March, would give GGP shareholders a $23.50 cash dividend, and a choice of one share of Brookfield stock or ownership in a new REIT for every GGP common share. The total cash consideration was valued at $9.25B, and the overall deal is valued at $15B. Brookfield already owned 34% of GGP stock.

The two REITs have been in merger discussions since last year. Brookfield's first offer in November 2017, with a cash consideration of $7.4B, was considered too low by GGP shareholders and rejected. Unibail's $16B acquisition of Westfield in December 2017 led Brookfield to go back to the drawing board.

When Brookfield confirmed its sweetened offer in March, analysts argued the bid was still low and would result in undervaluing, and repricing, of Class-A malls. Brookfield hopes to replicate the success it had acquiring GGP-spinoff Rouse two years ago. Brookfield was able to unlock value in Rouse's land holdings for residential, office and commercial redevelopment.

Under CEO Sandeep Mathrani, GGP recovered from the Great Recession with a diversification strategy focused on acquiring and operating street-level retail assets in high-traffic urban core locations.

Brookfield's shareholders already approved the deal, which is expected to be completed next month.