Thomas Properties Group Inc. announced that its stockholders have approved its merger with Parkway Properties Inc., which is expected to close on Thursday.

The Los Angeles commercial real estate company in September accepted an offer from Orlando, Fla.-based Parkway valued at $1.2 billion. At Tuesday’s special meeting, about 99 percent of the votes, which represented 87 percent of total outstanding common and limited voting stock, approved the deal.

The deal gives shareholders $294 million in Parkway stock, which trades under the ticker symbol “PKY” on the New York Stock Exchange. Parkway also will assume $752 million in Thomas Properties’ debt. As part of the transaction, James Thomas, Thomas Properties founder and chief executive, will become chairman of Parkway.