Why San Diego Is Becoming a Startup Hub
San Diego doesn’t get the spotlight. Silicon Valley gets the spotlight. Austin gets the spotlight lately too. But the numbers coming out of San Diego tell a different story, and honestly, it’s a better one than most people realize.
Let’s start with the big number. The city pulled in over $3.6 billion in venture capital in 2025, and it’s home to nearly 2,000 life science companies generating $56 billion in economic output. Fifty-six billion. From one city’s biotech scene alone.
And it’s not slowing down. San Diego’s whole startup ecosystem grew 19.4% in 2025, landing at 25th globally with 1,875 startups and total startup funding topping $4.81 billion.
Here’s the kicker though. In March 2026 alone, San Diego captured 11.3% of all national venture capital, pulling in $2.15 billion across just eight deals. Eight deals. That’s not breadth, that’s concentration. A huge chunk of that came from one company, Shield AI, which closed roughly $2 billion in combined financing that same month for its defense autonomy work.
So when people ask why the top startups in San Diego deserve more attention, that’s the answer right there. This isn’t a city chasing hype cycles. It’s a city with decades of research infrastructure quietly producing some of the best-funded startups in the country. Nobody’s throwing a parade about it. But the money doesn’t lie.
What Makes San Diego’s Startup Scene Different
Every startup city has its thing. San Diego’s thing is science. Not “tech that touches science.” Actual, hardcore, lab-coat science.
The city is globally recognized as a biotech powerhouse, second only to Boston and the San Francisco Bay Area, with research institutions like the Salk Institute, Scripps Research, and Sanford Burnham Prebys creating an environment for healthcare innovation that’s hard to replicate anywhere else. You can’t just build that infrastructure overnight. It took decades.
The reality is, the numbers back this up in a big way. San Diego’s biotech cluster now includes over 1,400 life science companies, employs more than 71,000 people directly, and generates $54.1 billion in economic output as of 2026. That kind of density doesn’t happen by accident. It happens because the talent pipeline never stops.
With 3.2 million square feet of new lab and research space coming online by the end of 2025, and UC San Diego leading the nation in STEM graduates, the city just keeps feeding itself. On the funding side, Series A startups here typically raise $5 to $15 million, backed by local firms like Avalon Ventures, Correlation Ventures, and Finistere Ventures. That’s a slower, more deliberate rhythm than what you’d see in Austin or DC. But biotech research is expensive and slow by nature. So the funding pattern just reflects the work.
Shield AI: Building AI Pilots for Modern Defense
Shield AI is the biggest funding story to come out of San Diego this year. Full stop.
In March 2026, the defense startup raised $1.5 billion in Series G funding at a $12.7 billion valuation, more than doubling its previous valuation of $5.6 billion. The round was co-led by first-time investors Advent International and JPMorganChase’s Security and Resiliency Initiative, alongside a separate non-dilutive $500 million preferred equity deal with Blackstone. Combine those two and you get the roughly $2 billion figure that basically defined San Diego’s entire VC quarter.
Founded in 2015 by brothers Brandon and Ryan Tseng along with technical fellow Andrew Reiter, Shield AI builds Hivemind, AI pilot software that lets drones and fighter jets fly autonomously. The company is projecting more than $540 million in revenue for 2026, growing at 80% or higher year over year, and its V-BAT drone has already flown real missions in Ukraine. Earlier in the year, a $240 million round brought in defense contractors L3Harris and Hanwha Aerospace as investors, pushing the valuation to $5.3 billion at the time. Fast company. Faster money.
Iambic Therapeutics: Speeding Up Drug Discovery with AI
Drug discovery is slow. Painfully slow. Iambic Therapeutics is trying to fix that.
The San Diego company’s AI-driven platform is built to compress a process that traditionally takes 10 to 15 years down to just a few. Think about that for a second. An entire industry’s timeline, cut by more than half.
Founded in 2019 by CEO Tom Miller and Fred Manby, Iambic has raised $334 million in total funding as of a Series C round in April 2026. Its pipeline targets breast cancer and other HER2-driven cancers, and it’s running a research collaboration with Lundbeck on migraine treatment. A recent oversubscribed round of over $100 million drew Abingworth, Sequoia, Mubadala, the Qatar Investment Authority, and Regeneron Ventures. That’s a serious investor list for a company most people outside biotech have never heard of.
Avenzo Therapeutics: Developing Next-Generation Cancer Drugs
Avenzo Therapeutics has moved fast. Faster than most companies at this clinical stage.
The San Diego oncology developer closed a $60 million Series B round led by OrbiMed and SR One Capital Management, pushing total funding to $446 million just three years after founding. Three years. $446 million. Let that sink in.
Founded in 2022 by Athena Countouriotis and Mohammad Hirmand, Avenzo develops targeted cancer therapies, CDK2 and CDK4 inhibitors for breast cancer, and antibody-drug conjugates for lung and urothelial cancers. The company has already filed three Investigational New Drug applications with the FDA and started two clinical trials, with a third close behind. It’s lonely being this early with this much riding on you. But the funding says investors aren’t worried.
Drata: Automating Security and Compliance
Nobody gets excited about compliance. Drata built a $2 billion company out of it anyway.
The San Diego-based automation platform has raised a total of $328.2 million, hitting a $2 billion valuation in December 2022 through a $200 million round led by ICONIQ Growth and GGV Capital. Founded in 2020 by Adam Markowitz, Daniel Marashlian, and Troy Markowitz, Drata helps companies streamline SOC 2 compliance with continuous, automated monitoring and evidence collection.
Here’s the thing about compliance software. It’s boring until you need it, and then it’s everything. Drata hit an estimated $98 million in annual recurring revenue by January 2025, growing to 7,000 customers with 100% year-over-year growth in EMEA. Salesforce Ventures backed the company. So did Microsoft CEO Satya Nadella, personally. That’s not a small vote of confidence.
Kandji: Simplifying Apple Device Management
Remote work broke a lot of IT departments. Kandji built a business fixing exactly that.
The San Diego platform raised $100 million in Series C funding led by Tiger Global, valuing the company at $800 million. That was Kandji’s third funding round in just twelve months, bringing total funding raised to $188.5 million at the time. Three rounds. One year. That’s not normal pacing, and it tells you something about how hot enterprise Apple management got.
Since then, the company has kept climbing. Total funding now sits at $284.4 million across five rounds, with valuation reaching $850 million. Kandji now works with around 1,000 customers across 40 industries, including Noom, Allbirds, GitHub, and Zoom. Not bad for managing MacBooks.
ClickUp: One App to Replace Them All
ClickUp is San Diego’s clearest unicorn story, and it started as an internal tool nobody meant to sell.
The company relocated to San Diego in January 2020, and by October 2021 it had raised $400 million in Series C funding at a $4 billion valuation. Founded in 2017 by Zeb Evans and Alex Yurkowski, ClickUp combines tasks, docs, chat, and goal tracking into one platform meant to replace half the apps on your desktop.
The reality is, “replace everything” pitches rarely work. ClickUp’s did. The company has raised $537.5 million in total funding across five rounds and now reports around $300 million in annual recurring revenue, serving 100,000 customers. That’s a real business, not just a good idea with a big check behind it.
Seismic: Powering Sales and Marketing Teams
Seismic doesn’t get talked about much outside sales circles. But it’s been quietly building for over a decade.
Founded in 2010 by Nasser Barghouti, Doug Winter, Ed Calnan, and Fred Xie, the San Diego company has raised $440 million total from investors including Permira, Lightspeed Venture Partners, and General Atlantic, reaching unicorn status along the way. Fifteen years of building. Not a flashy, overnight story. Just steady growth.
Seismic now serves more than 2,000 organizations worldwide with sales enablement tools, content management, coaching, and analytics for customer-facing teams. A 2020 Series F round led by Permira valued the company around $1.6 billion at the time, and Seismic has kept raising since, including a debt round in 2024. Slow and steady, but it worked.
Element Biosciences: Making Genome Sequencing Affordable
Genome sequencing used to be expensive. Prohibitively so for a lot of labs. Element Biosciences decided that was a solvable problem.
The San Diego company announced over $277 million in Series D funding in July 2024, led by Wellington Management, pushing cumulative funding past $680 million. And they weren’t done. In June 2026, Element announced an upsized Series E round including $175 million from longstanding investor Samsung Electronics, aimed at pushing its genomic technologies further into the market.
Founded in 2017 by Molly He and Michael Previte, the company built the AVITI benchtop sequencer. Here’s the number that matters most. Less than a year after its 2022 launch, the technology helped bring the cost of whole genome sequencing down to $200. Two hundred dollars. That used to cost thousands.
BlossomHill Therapeutics: Designing Smarter Cancer Medicines
BlossomHill Therapeutics didn’t start from zero. Its founders had already done this once before, successfully.
The San Diego firm was founded in 2020 by Jean Cui and Peter Li, who previously cofounded Turning Point Therapeutics, later acquired by Bristol Myers Squibb. That kind of track record gets attention fast, and it did.
BlossomHill closed an $84 million Series B extension led by Janus Henderson Investors, Brahma Capital, and BioTrack Capital, bringing total capital raised to $257 million. The funds are accelerating two lead clinical programs: BH-30643, a first-in-class EGFR inhibitor for lung cancer, and BH-30236, a CLK inhibitor for acute myeloid leukemia. Two shots on goal. Both aimed at cancers that badly need better options.
Gretel: The Synthetic Data Startup Nvidia Wanted
Most companies on this list are still writing their story. Gretel already has an ending, and it’s a good one.
Founded in 2019 in San Diego by Ali Golshan, Alex Watson, Laszlo Bock, and John Myers, Gretel built a platform for generating synthetic, privacy-preserving data to train AI models. Before its acquisition, the company had raised a total of $65.5 million, including a $50 million Series B round led by Anthos Capital.
Then Nvidia came knocking. In March 2025, Nvidia acquired the San Diego startup and its roughly 80-person team in a nine-figure deal exceeding Gretel’s most recent $320 million valuation. It’s a clean example of a San Diego startup building something a trillion-dollar company actually wanted to own outright. That doesn’t happen often.
Top Industries Driving San Diego Startups in 2026
Biotech is still the backbone here, and it’s not close. San Diego’s ecosystem ranks 7th globally for healthtech, with the top three healthtech unicorns alone raising more than $2.08 billion.
But defense tech is the newer, faster story. Shield AI’s raise this year practically defined San Diego’s entire VC quarter on its own, which tells you how concentrated capital has gotten around autonomous defense systems. And let’s be honest, that kind of concentration is a little unusual. Most ecosystems don’t have one company move the whole needle like that.
Meanwhile, ClickUp, Seismic, Drata, and Kandji prove San Diego isn’t a one-trick biotech town anymore. Six startups here have hit unicorn status, with the top three collectively raising more than $9.8 billion.
How These Startups Are Funded
The investor pattern leans heavily on specialist life sciences funds working alongside major generalist firms. OrbiMed shows up again and again: Iambic, Avenzo, and BlossomHill, all three. Meanwhile, Tiger Global and Andreessen Horowitz anchor the software side through Kandji and ClickUp.
Venture capital in San Diego’s biotech sector rebounded to $4.8 billion in 2025, and major recent acquisitions, including Novartis’s $12 billion purchase of Avidity and Roche’s $1.5 billion acquisition of Poseida, show sustained global interest in San Diego innovation. That’s not a small signal. It tells founders and investors that a San Diego biotech startup, built well, can attract acquirers with genuinely enormous checkbooks.
What’s Next for San Diego’s Startup Ecosystem
San Diego heading into the rest of 2026 looks strong on both fronts, the old strength and the new one. The biotech engine keeps expanding physically, with new lab space coming online to support a growing base of life science companies. And defense tech has become a real second pillar, not just a side story, with Shield AI alone reshaping the city’s national VC share in a single quarter.
Despite a more complicated funding environment nationally, including pressure from NIH funding constraints, San Diego’s biotech cluster remains one of the largest and most productive in the country. It’s not an easy environment right now. But the fundamentals haven’t cracked.
Combine that with a growing list of well-funded SaaS unicorns and at least one clean, high-profile acquisition story in Gretel, and the case for watching the top startups in San Diego closely just gets stronger every quarter. For founders, investors, and anyone paying attention, the throughline here is different from Austin or DC. San Diego’s biggest wins aren’t chasing trends. They’re built on decades of scientific infrastructure, elite research talent, and a funding culture that rewards people willing to solve genuinely hard problems, whether that’s curing cancer, sequencing a genome for $200, or building an AI pilot that can fly a fighter jet.
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