Initial PSA equity was provided by the founding investors, a group of prominent local individuals and families. These included Howard Wright and Grousemont Associates (family of famed contractor Howard S. Wright II), Howard Schultz (founder of Starbucks), Jeff Brotman (founder of Costco), Orca Bay Capital Corp. (investment entity of John McCaw), Gary Waterman (co-founder of LaSalle Partners), and the R.D. Merrill Company (family of Virginia Wright).

In 1996, PSA and the Multi-Employer Property Trust (MEPT), a pooled equity real estate fund, formed Pine Street Development L.L.C. (PSD) to reflect new equity participation by MEPT. At the end of 2000, when the development work of PSD was completed, PSG was formed by the former PSD management group to provide property management services for the PSD properties and launch new development initiatives.