Correction, 12/20/13, 9 a.m. EST: The original version of this story failed to note that Goodwin Procter partner Gil Menna is leading the firm’s team advising Essex Property Trust in connection with this transaction. The sixth paragraph of the story has been revised to reflect that. We regret the error.

Real estate investment trust Essex Property Trust said Thursday it has agreed to acquire fellow California-based REIT BRE Properties in a cash-and-stock deal valued at $4.34 billion. Goodwin Procter is advising Essex on the transaction, while BRE has turned to Latham & Watkins as its outside counsel on the matter.

Once the deal is complete, the resulting entity will own approximately 56,000 multifamily units spread across 239 properties in California and Seattle and will have a total market capitalization of approximately $15.4 billion. “The combined company will be the largest and only publicly traded pure play apartment REIT on the West Coast,” Essex president and CEO Michael Schall said in announcing the acquisition. (Schall will retain those titles after the merger closes.)

The transaction calls for each common share of San Francisco–based BRE’s stock to be converted to 0.2971 newly issued shares of Essex common stock and $12.33 in cash. Under those terms—and based on the closing price of BRE shares as of Wednesday—the deal values each BRE share at $56.21. After the deal is finalized, Essex’s equity holders will own roughly 63 percent of the combined company’s equity, while BRE equity holders will own the balance.

Palo Alto–based Essex said it has $1 billion of committed financing on hand to fund the cash portion of the transaction, and it is still considering how to raise the rest of the required cash. Asset sales and joint ventures are among the options it is weighing.

The boards of directors of both Essex and BRE have approved the deal, which calls for three BRE board members to join what will be the 13-member board of the newly combined company. The merger, which is expected to close in the first quarter of 2014, is subject to the approval of the two companies’ shareholders and customary closing conditions.

The Goodwin team advising Essex is being led by Gil Menna, who heads the firm’s real estate capital markets practice, and also includes debt finance partner Jennifer Bralower; M&A and corporate governance partners John Haggerty and Suzanne Lecaroz; tax partners Mark Kirshenbaum and Kelsey Lemaster; real estate capital markets partners Dean Pappas and Craig Todaro; and executive compensation partner Marian Tse.

A Goodwin spokesman says the firm has advised Essex on previous matters, but did not provide specifics. He declined a request for additional details about the firm’s work on the matter.

Jordan Ritter is Essex’s general counsel.

The Latham team advising BRE, meanwhile, is being led by corporate partners William Cernius and John Newell. Other Latham lawyers working on the matter include employee benefits and compensation partner James Barrall and counsel Scott Thompson; tax partners Michael Brody and Ana O’Brien; finance partners Glen Collyer and Kimberly Posin; real estate partner David Meckler; and environmental partner Christopher Norton.

The Latham team also includes corporate associates Anitha Anne, Aneta Ferguson, Ashley Flor, Darren Guttenberg, William Hackett, Jeffrey Holgate, John Raney, Brett Urig, David Wheeler and Michael Young; environmental associate Charles Anthony III; employee benefits and compensation associate Julie Crisp; finance associate Josh Holt; real estate associate Alex Johnson; and tax associate Tali Weiss.

Latham declined to comment about its work on the transaction.

Ballard Spahr is serving as specialty Maryland counsel to BRE in connection with the deal. The Ballard Spahr team includes business and finance partner Douglas Fox, of counsel John (Tad) Bashore II and associate Lauren Ziegler. A firm spokeswoman notes that, like most REITs, both BRE and Essex are incorporated in Maryland and that the companies wanted lawyers who understood the intricacies of Maryland corporate law, which is why Fox’s team was brought in.

BRE’s in-house team on the matter is being led by general counsel Kerry Fanwick.