Item 2. Properties

We lease approximately 4.9 million square feet of office space worldwide, pursuant to leases with expiration dates through March 2031.

We lease approximately 580,000 square feet for our headquarters in Bellevue, Washington, the majority of which ends by mid-2020 with the exception of 70,000 square feet which expires in January 2023. We also lease approximately 1.5 million square feet of office space for our domestic operations in various other cities and locations pursuant to leases with expiration dates through March 2031.

We also lease approximately 2.8 million square feet of office space for our international operations in various cities and locations pursuant to leases with expiration dates through June 2030.

In addition to our leased space, on April 30, 2015, we acquired our future corporate headquarters, consisting of multiple office and lab buildings located in Seattle, Washington. The build out of the headquarters is significant as we convert lab facilities into office space. We expect employees to begin to move into the new campus at the end of 2019.