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Shield AI, a San Diego-headquartered unicorn defense tech company, raised the largest venture capital round among local tech companies in 2025.
SAN DIEGO — 11 San Diego-based companies secured venture funding rounds totaling more than $100 million-plus in 2025, according to data collected by Connect.
The largest round went to Shield AI, which raised $240M in a Series F round at a $5B valuation. Crystalys Therapeutics followed, emerging from stealth and announcing a $205M Series A round in September 2025.
Deal activity in San Diego declined slightly, with deal count down 6% year over year, from 161 to 152.
Despite a more selective investment environment, dozens of San Diego life science companies raised mega-rounds in venture capital. A total of three companies went public, including Aardvark Therapeutics, Carlsmed and Aptera Motors.
The local startup ecosystem ranked No. 7 in venture capital funding behind Seattle and Austin, according to Carta, which evaluated total seed through Series C rounds across major U.S. ecosystems in 2025.
Gary Steele (right) with Michael Yang (center), Chief Legal Officer, and Ryan Tseng, Chief Strategy Officer.
Thomas Miller, co-founder and CEO of Iambic Therapeutics. The company uses generative AI to design and discover differentiated drugs, accelerating the path from discovery to clinic.
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Crystalys Therapeutics, a biotech focused on therapeutic products, raised $205M.
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Timberlyne, a biotech focused on autoimmune disorders, raised $180M.
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Protego Biopharma, a biotech focused on small molecule therapy, raised $130M.
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Aspen Neuroscience, a biotech focused on unmet medical needs, raised $115M.
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RayThera, a biotech focused on developing immunology drugs, raised $110M.
Sarah Boyce, CEO of Avidity Biosciences. She led a successful IPO in June 2020, advanced multiple therapies into clinical development, and expanded the company’s RNA technology platform ahead of its October 2025 acquisition.