The future of the merger between Thomas Properties Group (NYSE: TPGI) and Parkway Properties (PKY#) will hang in the balance on December 17. That date was set today by Thomas Properties for a special meeting of its shareholders in order to vote on the marriage of their company with the real estate investment trust. The meeting will take place at 10 a.m. local time in downtown Los Angeles.

The record date for Thomas Properties shareholders to participate in the vote has been set to the close of business on November 11.

The two companies signed a definitive stock-for-stock merger agreement valued at roughly $1.2 billion in early September. Under the terms of the deal, Thomas Properties shareholders will receive 0.3822 shares of Parkway stock per each share of Thomas Properties stock they own. The merger is expected to close by the end of this year, pending the shareholder approval.

At the moment, Thomas Properties has just under 47 million shares outstanding, which most recently closed at $6.92 per share. For Parkway, those figures are 68.6 million and $18.33, respectively.