Edison-based Mack-Cali Realty Corp. announced today it has agreed to sell its suburban Philadelphia office portfolio, consisting of 15 commercial office totaling 1.6 million square feet, in a $233 million deal.

The sale will involve various joint ventures with a fund sponsored by Keystone Property Group.

The portfolio, which includes three land parcels, will sell for about $233 million in cash, mortgage and subordinated interests. Mack-Cali will participate in management fees and 50 percent of value creation above certain hurdle rates. Mack-Cali will also receive majority interest in a land parcel in Bala Cynwyd, Pa., for multifamily residential development.