Interesting stats out of the Colliers research department, confirming a trend that has been building for some time. Sublease space as a percentage of the market in Silicon Valley has shot up drastically over the past year, now making up nearly a third of total inventory. In Palo Alto, the strongest submarket in the region, the increase is even more pronounced (though a bit skewed by a few large short term availabilities).
Sublease inventory has so far been kept under control by strong demand for short term leases. Worth keeping an eye to see if this trend holds.