Keck Medicine of USC now occupies three Pasadena addresses after opening a back-office operations hub at The Walnut Plaza, 215 N. Marengo Ave., the health system announced in June 2026.

The office is not patient-facing. It houses administrative staff supporting healthcare operations across the system; Keck Medicine did not specify which departments moved there or how many employees work at the site.

The new location joins two clinical facilities on South Fair Oaks Avenue. The anchor is a four-story, 100,000-square-foot outpatient building at 590 S. Fair Oaks Ave. that opened October 3, 2025, offering more than 15 specialties including oncology, cardiovascular care, orthopedics, neurology, and an ambulatory surgery center. That building more than doubles Keck Medicine's outpatient capacity in Pasadena, according to the health system. A smaller, 18,000-square-foot clinic at 625 S. Fair Oaks Ave. handles memory care, endocrinology, ophthalmology through the USC Roski Eye Institute, primary care, and dermatology.

The three-site footprint fits a broader eastward push. Shawn Sheffield, Keck Medicine's chief strategy officer, described the trajectory in a 2022 essay as expansion along the "210 corridor" from Pasadena through Arcadia and into the Inland Empire. The system absorbed Methodist Hospital of Southern California in Arcadia in July 2022, renaming it USC Arcadia Hospital. The California Attorney General required a $200.7 million infrastructure investment as a condition of that deal.

The health system's pending LEED Platinum certification for the Fair Oaks building, if granted, would make it the second USC-built project to earn that designation, according to Keck Medicine.