Meta listed a massive 435,000 square feet, all of its office space, at SF's 181 Fremont Street for sublease. Just by itself, the listing adds half a percentage point to SF's office vacancy rate, which was already a record high 27.6% at end of 2022, per CBRE.
Source:
https://sfchronicle.com/tech/article/Meta-lists-massive-435-000-square-foot-S-F-17729198.php