Having completed several projects for GlaxoSmithKline, Liberty responded to GlaxoSmithKline's request to build a new headquarters for its U.S. Operations in downtown Philadelphia. In order to accommodate their need for a flexible facility that could be expanded at a later time, Liberty developed an 8-story, 215,300 square foot building with the ability to expand vertically by an additional eight stories. Liberty completed the $36 million facility - known as Three Franklin Plaza - in late 1999, making it the first major Center City office project in 10 years.

In 2003, Liberty completed another GlaxoSmithKline building: a 260,000 square foot distribution center in Greenville, South Carolina.