COMMITMENTS AND CONTINGENCIES We are sometimes involved in lawsuits, warranty claims, and environmental matters arising in the ordinary course of business. Management makes assumptions and estimates concerning the likelihood and amount of any potential loss relating to these matters. We are currently a party to various legal proceedings. We accrue a liability for litigation if an unfavorable outcome is probable and the amount of loss can be reasonably estimated. If an unfavorable outcome is probable and a reasonable estimate of the loss is a range, we accrue the best estimate within the range; however, if no amount within the range is a better estimate than any other amount, the minimum within the range is accrued. Legal fees related to litigation are expensed as incurred. Other than as described below, we do not believe that the ultimate outcome of these matters, either individually or in the aggregate, could have a material adverse effect on our financial position or overall trends in results of operations; however, litigation is subject to inherent uncertainties. Also under our leases, tenants are typically obligated to indemnify us from and against all liabilities, costs and expenses imposed upon or asserted against us (1) as owner of the properties due to certain matters relating to the operation of the properties by the tenant, and (2) where appropriate, due to certain matters relating to the ownership of the properties prior to their acquisition by us. Under the terms of certain partnership agreements, the partners have the right to exchange their operating partnership units for cash or the same number of our common shares, at our option. A total of 799,962 downREIT operating partnership units are outstanding which have a total fair value of $106.8 million , based on our closing stock price on March 31, 2017 . On January 12, 2017 , we exercised our purchase option on non-controlling interests in San Antonio Center for $2.6 million of cash and 44,195 of downREIT operating partnership units.