About this programme
HAX is a hard tech startup development program run by SOSV, a multi-stage venture fund founded in 1995 by Sean O'Sullivan that manages over $1.6B in assets under management. HAX makes multi-stage investments in pre-seed and seed companies addressing challenges in human and planetary health, and operates alongside SOSV's other program, IndieBio.
The program backs founders working on physical, engineering-heavy products rather than software. HAX describes its focus with a simple test: "if you drop it on your foot does it hurt? If the answer is yes, it's probably hard tech." Three areas get particular attention: climate tech (renewable energy, energy storage, battery recycling, advanced materials), healthcare (cancer diagnostics, medical devices, molecular diagnostics), and industrial independence (manufacturing automation, robotics, biomanufacturing, circularity).
HAX runs hands-on engineering and manufacturing support out of a 35,000 sq ft facility in Newark, New Jersey, with additional offices in Shenzhen and Pune handling engineering and manufacturing, and a Tokyo office working mainly with Japan-based teams. The program combines capital with in-house mechanical, electrical and mechatronics engineering, industrial design, supply-chain sourcing, and go-to-market support.
The program is not a fixed-length cohort in the traditional accelerator sense: teams are admitted on a rolling basis, typically two to three teams a month, and the program itself runs six to eighteen months depending on the technical complexity of what the founders are building.
How it works
HAX's first investment is $250,000, structured as $150,000 in cash plus $100,000 in in-kind support (engineering staff, workshop and bio-lab access, prototyping equipment), paid out at thirty-day intervals rather than as a lump sum.
The investment instrument is a Post Money SAFE with no valuation cap; instead the SAFE specifies SOSV's target ownership outright, converting to a pre-negotiated equity stake at a later priced round.
Payments are tranched deliberately: HAX states this is because "hardware is capital intensive" and founders need to establish constraints, set milestones, and solve problems creatively in the early stages rather than receive all the capital up front.
SOSV can participate in follow-on rounds beyond the initial check, investing further "usually up to a Series C/D," with an aggregate total of up to $4M per company across the SOSV V and SOSV Select funds.
By the end of the program, HAX expects teams to have gone through multiple prototyping cycles, produced manufacturability-focused hardware, finalized their bill of materials and supply chain, built sales and marketing assets, secured customer pilots or paying customers, sharpened company strategy, and made key hires.
Who can apply
HAX looks for three things in an applicant: a validated problem established through direct customer discovery, a strong founding team combining engineering ability with customer focus, and a working prototype that demonstrates technical feasibility — concept-stage ideas without a prototype are cited as a common reason for rejection.
The program is exclusively for hardware companies; non-hardware products are explicitly listed as a rejection reason. Other stated rejection reasons include a problem too small to support venture-scale returns, an already-crowded market, lack of defensibility, and a sole founder relying on contracted (rather than in-house) engineers.
The official FAQ does not state a geography or citizenship restriction, a remote-vs-in-person requirement, or visa-sponsorship terms — these were not confirmed on the official pages and are not stated here.
How to apply
- Submit an application through HAX's official channels; applications are typically reviewed within two weeks.
- If selected, HAX sends an interview request by email.
- Go through a minimum of three and maximum of four interviews, conducted mostly remotely.
- Receive a decision, typically within two weeks of the first interview — the full process usually completes within about a month, though high application volumes can extend this.
- Teams are admitted on a rolling basis (roughly two to three teams per month), not against a single fixed intake deadline.
Frequently asked
How much does HAX invest and on what terms?
The first investment is $250,000: $150,000 in cash and $100,000 in in-kind support (engineering staff time, workshop/lab access, prototyping equipment). It is structured as a Post Money SAFE with no valuation cap that specifies SOSV's target ownership outright, converting to equity at a later round. Payments are released at thirty-day intervals rather than all at once.
Can HAX invest again after the initial check?
Yes. SOSV can participate in follow-on rounds, usually up to a Series C/D, with an aggregate total of up to $4M per company invested across the SOSV V and SOSV Select funds.
What kind of companies does HAX back?
Hardware companies in three focus areas: climate tech (renewable energy, energy storage, battery recycling, advanced materials), healthcare (cancer diagnostics, medical devices, molecular diagnostics), and industrial independence (manufacturing automation, robotics, biomanufacturing, circularity). HAX's own shorthand for the category is "hard tech" — physical products, not software.
What do I need to have ready before applying?
A validated problem backed by customer discovery, a founding team with real engineering ability and customer focus, and a working prototype that demonstrates feasibility. Concept-only ideas without a prototype, and non-hardware products, are both cited as common reasons applications are rejected.
What does the application and interview process look like?
Applications are reviewed within roughly two weeks. Selected teams are invited by email to a minimum of three and maximum of four interviews, conducted mostly remotely, with a decision typically arriving within two weeks of the first interview.
How long does the program run and where does it happen?
Between six and eighteen months, depending on the technical complexity of the product. HAX's primary hands-on workshop facility is 35,000 sq ft in Newark, New Jersey, with additional engineering and manufacturing offices in Shenzhen and Pune, and a Tokyo office focused on Japan-based teams.
What support does HAX provide beyond capital?
In-house mechanical, electrical and mechatronics engineering, industrial design, supply-chain sourcing, marketing/creative asset support, and business development and fundraising strategy help, plus investor introductions.
What happens after a startup completes the program?
Alumni keep access to HAX's internal Slack channel, founder portal, wiki, workshops, labs and coworking space until they raise a Series A, along with continued mentorship on R&D, manufacturing and investor introductions.
Are there other perks besides the cash investment?
Yes — HAX lists a package of partner perks including AWS and Google Cloud credits and discounts on tools like Solidworks and HubSpot, with a stated total value of $1M per team.
Reviewed 2026-08-16. Programmes change — confirm current eligibility, amounts and deadlines on the official page before you apply. CapEasy is a private consultancy and is not affiliated with any government authority.