
.406 Ventures
470 Atlantic Avenue, 12th Floor, Boston, Massachusetts, 02210, United States
Overview
.406 Ventures is an early-stage venture capital firm that invests in innovative Information Technology ("IT") and services companies founded by the finest entrepreneurs. They are a veteran team of industry entrepreneurs, operators and investors who apply real world experience, deep industry knowledge and networks, and strong company-building skills to create value for our entrepreneurs and investing partners. .406 Ventures typically are the lead, first institutional investor in early-stage and de novo investments in market-changing IT Security and Infrastructure, Technology-Enabled Business Services, and Next-Generation Software companies.
- Total investments
- 165
- Lead investments
- 55
- Investments · 12mo
- 7
- Active investors
- 8
Sector focus
- Financial Services
- Impact Investing
- Venture Capital
Investment portfolio
- Mindgard
Participated · Series A · Aug 2026
Mindgard operationalizes AI security research and offensive-security expertise through a Security Platform that performs Shadow AI discovery, AI red teaming, and run-time AI protection across models, agents, and applications. The company was spun out of over a decade of AI security research at Lancaster University and is headquartered in Boston and London. Mindgard's platform has been used to uncover and publicly disclose more than 150 high-impact security and safety vulnerabilities in widely used AI products, including a zero-day code execution vulnerability in Cursor IDE, a trusted workspace flaw in Google Antigravity, and image-generation guardrail failures in ChatGPT. Its customer base includes a large number of Fortune 2000 companies and AI innovators across financial services, pharmaceuticals, gaming, digital services, semiconductors, and healthcare. The company plans to scale product, engineering, sales, and marketing following its $30M Series A to meet significant enterprise demand.
- InStride Health
Participated · Series C · Jun 2026
InStride Health delivers virtual specialty outpatient care for pediatric anxiety and obsessive-compulsive disorder using cognitive behavioral therapy with a focus on exposure therapy. It provides multidisciplinary care teams—typically a therapist, an exposure coach and a psychiatrist—that develop personalized care plans and communicate with patients and families via text, phone or video. The company serves patients ages seven to 24 and currently operates in 17 states, having treated more than 5,000 patients. Reported outcomes include 97% of graduates showing overall clinical improvement and over 99% of patients remaining out of the hospital one year after discharge. Caregiver impacts reported include an 81% reduction in caregiver stress and more than 90% reporting reduced missed work. InStride aims to expand access to evidence-based specialty care while preserving its clinical outcomes as it grows into new and existing markets.
- Relai
Led · Seed · Jun 2026
Relai builds continual learning infrastructure for AI agents that uses a verifiable continual learning approach to turn failures, traces, evaluations and human feedback into replayable learning environments. Its platform identifies root causes and continuously optimizes prompts, tools, memory, workflows and models with online, in-loop regression control. The company has raised a total of $6.9M to date, including $5.4M in the reported Pre-Seed round and a prior $1.5M from Non sibi Ventures and TEDCO. Relai intends to use the new funding to expand its engineering team, further develop the platform, and prepare for broader go-to-market efforts. The company was founded by CSO Soheil Feizi and is based in Bethesda, MD.
- Big Health
Led · Equity · Feb 2026
Big Health builds evidence-based digital therapeutics, most notably SleepioRx for insomnia disorder and DaylightRx for generalized anxiety disorder, both of which are among just nine FDA-cleared Digital Mental Health Treatments (DMHTs). Its products are delivered directly to patients or through provider partners, integrate into clinical workflows, and are now eligible for national Medicare reimbursement via newly created G-codes. Backed by more than a decade of real-world use, the company reports serving over 750,000 individuals, with clinical studies showing up to 76 % of SleepioRx users and 71 % of DaylightRx users achieving meaningful symptom improvement. Recent partnerships with health systems such as Henry Ford and Northwell signal accelerating adoption. The company positions its digital solutions as scalable, first-line alternatives to pharmaceuticals, addressing the significant care-access gap for the roughly 20 % of U.S. adults with anxiety disorders and the one-third experiencing chronic insomnia. The fresh capital will be used to deepen provider relationships, expand reimbursement pathways, and reach millions more patients.
- Valerie Health
Participated · Series A · Dec 2025
Valerie Health embeds large-language-model and vision-language-model agents directly into a clinic’s existing EHR and communication systems to automate labor-intensive front-office work such as referral intake, fax processing, and appointment scheduling. Its orchestration layer routes each task according to clinic-specific rules and incorporates human review to deliver near-100% accuracy, cutting administrative costs by about 50% while boosting new-patient conversions by 5–7%. Across early marquee customers—including some of the nation’s largest independent provider groups—the platform has driven 6× ROI, brought referral processing times down to a median of 19 minutes, and eliminated inbox backlogs. Over the last six months, Valerie has grown revenue more than 5× (including a 3× expansion within existing accounts) and opened a second office in Chattanooga. The company plans to use fresh capital to build a comprehensive AI front office, add new workflows and modalities such as voice, expand embedded operations teams, and deepen analytics capabilities. Co-founders Peter Shalek (ex-AbleTo/Optum, Joyable) and Nitin Joshi (Uber Health, Stripe, Bridge) bring extensive healthcare operations and software-scaling experience. Total funding now stands at $39 million, supporting further product expansion and customer growth.