The attempt by Equity Residential to acquire a minority stake in the estate of Lehman's Archstone apartment portfolio for $1.325 billion is favorable news for apartment real estate investment trusts, Standard & Poor's said Tuesday. S&P affirmed its ratings on Chicago-based Equity Residential after the deal was announced and said pointed to the positive impact such a deal will likely have on the multifamily market. "S&P expects multifamily operating conditions will remain favorable for rated apartment REITs and support healthy occupancy and continued rent growth for at least the next one to two years," S&P said. Still, the transaction is subject to a right of first offer by an entity that represents the now defunct Lehman Brothers, which filed for Chapter 11 reorganization three years ago. Archstone is a privately-held owner, operator and developer of multifamily apartment properties. According to an SEC filing, Bank of America(BAC) and Barclays Capital sent Lehman Brother a notice of intent to sell its interests in Archstone. After receiving the notice, Lehman's argued the note does not include all of the information required to trigger a 10-day period that forces Lehman's to exercise its rights, according to a filing with the Securities and Exchange Commission. In a securities filing, the Estate of Lehman argues Equity Residential's "agreement with the banks is not an offer for 100% of the equity interests of Archstone and, therefore, it is inappropriate to imply that the purchase price and terms offered for 26.5% of the equity interests of Archstone would be offered for the entire enterprise." Lehman further noted it feels that the purchase price offered for Archstone is inadequate. In a securities filing, the entity said, "Lehman believes that a net asset valuation (or, if Archstone were to be broken up and sold in pieces) of the Archstone enterprise would suggest at least an additional $1 billion of value over the value for the entire Archstone enterprise that would be implied by such a purchase price." "Furthermore, Lehman believes that the EQR purchase price does not take into consideration the value of Archstone’s platform, including its management, which Lehman believes is the best in the industry, nor does it take into account Archstone’s valuable strategic position within the apartment industry," the filing stated. Write to Kerri Panchuk.