Pharmaceutical companies in California: the largest state market, made in the south and invented in the north

This report is for people looking at California drug companies as employers, partners, suppliers or sales targets. It counts plants with Census data, names registered sites from FDA's file and checks the largest listed companies in their 10-Ks. For the San Diego cluster in detail, see the San Diego pharmaceutical market report.

California against the other states

County Business Patterns (CBP) 2023, NAICS 3254 (Pharmaceutical and Medicine Manufacturing):

Every size class is published. The shape is wide at the bottom: 289 establishments with fewer than 20 employees, 111 with 20 to 99 and 91 with 100 or more. By product, 215 make finished-dose pharmaceuticals (325412, 29,567 employees), 132 make medicinal chemicals and botanicals (325411, 6,442), 73 make diagnostic substances (325413, 7,508) and 71 make biological products such as vaccines, plasma proteins and cell therapies (325414, 9,942).

Made in the south, invented in the north

"Not reported" means the Census Bureau published the total but flagged it as high-noise: the noise it adds for confidentiality moved the value by 5% or more. Counties with one or two plants aren't published at all.

What the plant count leaves out

A CBP establishment is one location with paid employees, so a company with several plants counts several times; the self-employed are excluded. Code 3254 counts manufacturing only, so research labs, head offices and distributors sit in other codes. In California those are bigger than the plants: 1,571 biotechnology R&D establishments (NAICS 541714) with 65,114 employees, and 1,742 drug wholesale establishments (NAICS 424210) with 38,998. Ventura County shows the gap: Amgen's headquarters is in Thousand Oaks, yet the county has only 7 drug manufacturing establishments, because a campus's offices and labs are counted in their own industries.

Sites in FDA's registration file

In FDA's Drug Establishments Current Registration Site (DECRS), the public list of sites registered to make, pack or test drugs for the US market, we counted 512 California registrations in the 30 October 2026 download: 259 that make finished drugs or active ingredients, 112 medical gas suppliers (our classification by firm name), 67 packers or relabelers, 40 testing labs and 34 others (medicated feed mills, PET imaging drug producers and sterilizers). Los Angeles County has 149, Orange and San Diego counties 66 each.

Gilead's 10-K describes three of those sites: La Verne makes AmBisome and packages and labels "the majority of our commercial products for distribution to the Americas and the Pacific Rim," El Segundo makes cell therapies, and Oceanside makes retroviral vectors. Registrations are filed by the companies and aren't FDA approvals.

Listed drugmakers headquartered in California

SEC EDGAR shows 193 listed companies in SIC codes 2833 to 2836 with a California business address, more than any other state. The 15 largest by revenue, each checked in its latest 10-K:

BioMarin's 10-K now gives San Rafael, though EDGAR still files it under Novato. Ardelyx, which EDGAR places in Fremont, gives Waltham, Massachusetts, on its 10-K cover, so it's left out. For how Amgen and Gilead rank globally, see the largest pharmaceutical companies.

Checking a California company

• State licences. The California Board of Pharmacy licenses wholesalers, third-party logistics providers and outsourcing facilities (in-state and nonresident), and its license verification page links a separate search for each. The board says its website can be accepted as verification of a licence.
• FDA record. FDA's Data Dashboard lists inspections, warning letters and recalls by site.
• The network. Biocom California has offices in San Diego, Greater Los Angeles, the Bay Area and Sacramento, a member directory and a Career Hub job board, and publishes an annual Life Science Economic Impact Report.

Selling to California drug companies

Worked example: an environmental monitoring lab

Illustrative example. The lab and its prices are invented; the counts come from CBP 2023.

Coastline EM Labs (coastlineem.example) tests air, surface and water samples for cleanrooms in Southern California.

1. Choose the region. Los Angeles, Orange and San Diego counties hold 281 of the state's 491 drug plants.
2. Choose the tier. Plants with 20 to 249 employees often outsource monitoring; statewide there are 149 of them, so the three counties likely hold around 85 (our estimate from their 57% share of all plants).
3. Do the arithmetic. Reaching 40 and signing 6 at $48,000 a year brings $288,000 of recurring testing.

Working out which plants run sterile or aseptic lines is the slow part; Bebop researches each account and explains why it fits.

Next step: compare a state where the plants are fewer but much bigger in the North Carolina pharmaceutical market report.