ONSET Ventures

ONSET Ventures was a storied early-stage venture capital firm founded in 1984 and headquartered in Menlo Park, California. The firm was co-founded by Terry Opdendyk, who served as Founder and General Partner across 30-plus years; David Kelley, the founder of IDEO; and Michael Levinthal. For nearly four decades ONSET specialized in seed and Series A investments in information technology and medical sectors — spanning infrastructure software, media, medical devices, drug delivery, mobile, diagnostics, and broader healthcare. The long-tenured partner bench included Rob Kuhling, who joined as Partner in 1987 following his time at Sun Microsystems, and Shomit Ghose. Over its lifetime ONSET raised nine funds and managed more than $1 billion in cumulative assets under management, backing more than 130 companies and producing four IPOs and 42 acquisitions. Notable exits include Adaptive Insights, the financial planning and analytics platform acquired by Workday for $1.55 billion; NeuroStar, an FDA-cleared transcranial magnetic stimulation device for major depressive disorder; CallidusCloud, a sales performance management platform acquired by SAP; and Apama Medical, a chronic-pain therapy company focused on basivertebral nerve treatment. The firm leads rounds and was particularly active at Series A with an average round size of approximately $8.8 million. ONSET Ventures was officially dissolved on November 27, 2023 and is no longer an active investor. Its website and portfolio documentation are maintained for historical reference. The firm's four-decade run across Silicon Valley's technology and medical-device buildout represents one of the most consistent early-stage track records of its era.