Mainstay Labs Inc.
ActiveBusiness · San Francisco, CA
At a glance
Public records place Mainstay Labs Inc. at 1 active location in 1 San Francisco office building. Locations include 400 MONTGOMERY ST (STE 950).
Public record — San Francisco
Office locations (1 active)
| Building | Suite / floor | Submarket | Since | Source | Match |
|---|---|---|---|---|---|
| 400 MONTGOMERY ST | STE 950 | San Francisco | Aug 2024 | SF registered business | address · medium |
Where does Mainstay Labs Inc. operate in San Francisco?
The earliest active record dates from Aug 2024.
Across San Francisco, 9,124 active business locations are matched to office buildings; Mainstay Labs Inc. accounts for 1 of them.
How does BuildingCensus know Mainstay Labs Inc. is at these addresses?
Each location is a business record whose premises address was matched to a county office parcel (record types on this page: SF registered business). The match method and confidence are shown on every row.
A record at an address is evidence that the business operates there, not a lease: records lag moves by months, and businesses without a local record at an address do not appear.
Frequently asked questions
Where are Mainstay Labs Inc.'s offices in San Francisco?
Public records place Mainstay Labs Inc. at 1 active location in San Francisco: 400 MONTGOMERY ST (STE 950).
How long has Mainstay Labs Inc. been at its San Francisco locations?
The earliest active record starts Aug 2024. Start dates are when the record was opened, which can trail the actual move-in.
Related
Data provenance — public records only
- San Francisco — Assessor secured roll (use classes, stories, areas, assessed values — California law excludes owner names from open data, and no bulk sale-price source exists), the universal registered-business roll with suite-level addresses, and current energy benchmarking joined by parcel.
Every fact on this page is drawn from the government records above — no listing sites, no scraped platforms, no third-party images. Facts from public records are uncopyrightable; each tenancy row carries its source and match confidence. Records can lag reality — a business-tax receipt or registration at an address is evidence of occupancy, not a lease confirmation.
Dataset updated . Locations from San Francisco business records matched to county office parcels.
About this data
Source: Assessor secured roll (San Francisco), as published October 11, 2026. See the methodology for how records are matched, cleaned and scored.
Cite as: BuildingCensus, “Mainstay Labs Inc. — San Francisco office locations”, https://buildingcensus.com/offices/sf/companies/mainstay-labs-inc (data as of October 11, 2026).