Daxos Portfolio Teardown · How We Underwrote It

Theta Neurotech

An intern teaching aid: this is our own investment logic, not diligence on an outside target. Product and stage from public sources; funding from Harmonic. Tagged throughout.

Theta Neurotech builds a wearable EEG that tries to predict seizures (not just detect them) — small sensors behind the ears feeding an on-device model that warns a patient ahead of an event. Pre-clinical. This one is simple to explain: it was primarily a founder bet. Mark found the founder unusually competent, deeply understanding of the mission, and genuinely connected to it. Every material claim is marked VERIFIED, CLAIMED, or UNVERIFIED.

Chicago, IL Neurotech / wearable EEG Pre-clinical Seed · ~$3M Portfolio position 17

Theta Neurotech thetaneurotech.com ↗

Neurotech · Seizure prediction
Pos. 17portfolio
Funding (Harmonic)
$3.0M · 2 rounds
Stage
Pre-clinical · pilot pending
Headcount
~4 · Chicago
Regulatory
Likely De Novo · multi-year

Why we invested

MARK'S STATED LOGIC Primarily a founder bet. Mark found the founder super competent, felt he deeply understood the mission, and saw a genuine, personal connection to it. We backed the person and their fit to the problem above all else — the classic seed-stage call where the team is the asset and everything else is still an option.

What the company is

CLAIMED Theta builds a wearable EEG system for seizure prediction: two small adhesive sensors worn behind the ears that stream brain signals to a phone, with an on-device model that flags pre-seizure changes and alerts the patient and caregivers roughly 30 to 60 minutes ahead. VERIFIED It is pre-clinical: retrospective algorithm validation is done, and a first-in-human pilot is planned with UChicago Medicine. No prospective human data, no FDA clearance, and no revenue yet. UNVERIFIED Our internal note says founded 2022; every public source says 2024 out of the Polsky venture challenge — worth reconciling.

What we probed in diligence

No DRA data room for this name — these are the honest hard questions a founder bet at this stage has to answer.

  1. Retrospective vs prospective. Hospital-EEG accuracy rarely survives contact with a noisier, fewer-channel, ambulatory wearable. Does behind-the-ear EEG capture enough to hold ~89% sensitivity in the real world?
  2. Specificity / alarm burden. Sensitivity alone means nothing without the false-positive rate. A device that cries wolf gets taken off. What is specificity, and how many alerts per day?
  3. FDA path and timeline. A predictive device likely has no clean 510(k) predicate (De Novo). What class, what pivotal trial size, how many years and dollars to clearance?
  4. Reimbursement. No CPT code for consumer seizure forecasting today. Cash-pay wearable or prescription/DME path? It changes the whole model.
  5. Competition and durability. Empatica is FDA-cleared but detects convulsive seizures rather than predicting; NeuroPace is an implant. Is a ~35-minute prediction window a defensible moat or leapfroggable?
  6. Runway to proof. ~$3M and four people — enough to fund the UChicago pilot and generate the prospective data the next raise needs before cash runs out?

Bull case

Bear case

Key risks

Our verdictA high-risk, early-stage medical-device bet made the honest way: on the founder. There is a genuine unmet need and a promising algorithm, but everything hinges on whether retrospective accuracy survives a real-world wearable and an FDA-legible trial. We underwrote it as a small, asymmetric seed position on team, mission-fit, and category timing — a capital-efficient path to one clarifying milestone (the UChicago prospective pilot). It is not a business yet; it is a science-and-regulatory option, and the next data readout is the whole ballgame. The teaching point: when you back the person, you are buying their judgment through many pivots — so the founder read has to be right.
Pos. 17portfolio