Brain Surgery Was the Easy Part.

Firstly, dear reader, I apologize for the tardy post. I had a crazy Monday. I expect to be posting once a week every Monday, and if I miss a day you can expect me to post on Tuesday. I have a fun one for you today, let’s get into it.

Neuralink just raised a ton of money, a billion dollars across all rounds, and they are not alone. Precision Neuro, towards the end of last year, raised $102 million, while Synchron, already in humans, secured $75 million from high-profile backers including Gates, Bezos, and others in late 2022. Paradromics is completing its high-bandwidth interface in first-in-human trials. Neurable, Blackrock, and a dozen others are in the mix too, hiring, building, and moving forward.

If you zoom out, one thing becomes obvious: the invasive neurotech space is heating up, and investors are throwing cash in to fuel the flame.

Most of these companies are still in R&D or pilot stages, but the direction is clear. The billion-dollar brain interfaces are coming. Sooner than we think, they’ll move from clinical trials to commercial products. Devices will need to be manufactured at scale, implanted routinely, and supported for years.

That’s when things get real.

This post intends to be a reality check for companies building invasive BCIs. Because while scientific breakthroughs and flashy demos get the headlines, productionizing and scaling are where most deep tech startups fail. Especially in neurotech, where the margin for error is zero and the product lives inside someone’s brain.

Let’s talk about what actually needs to happen before you scale.

Here’s how it often goes: a small team of brilliant engineers and scientists designs a BCI, tests it in preclinical settings, gets a few successful implants, and assumes they’re ready to scale. But what worked ten times in a controlled setting with hand-built tools and in-house expertise does not scale to a thousand surgeries at hospitals you don’t control, with surgeons you didn’t train.

That early success is misleading. It’s built on proximity and heroics. Engineers hover over operating rooms. Signal quality is hand-optimized. Failures are patched in real time. It’s impressive, but not sustainable.

Scaling doesn’t just mean doing more. It means doing it reliably, affordably, and independently. When your device is no longer being implanted by the team that built it, can the results still hold?

That’s the question that will make or break the companies I mentioned above.

In the early days, most BCI prototypes are lab-built. Hand-soldered under microscopes. Custom fitted. Delicate. Built with rare materials that were chosen for performance, not supply chain stability.

None of that works at scale.

As soon as you try to manufacture at volume, you run into harsh new constraints: materials must be biocompatible, components must be reproducible at micron-scale tolerances, processes must be GMP compliant, and everything has to pass regulatory scrutiny.

This is usually when folks realize that their prototype, while functional, was never actually manufacturable. They go back to the drawing board to redesign around scalability, cost, and compliance. Entire engineering roadmaps get rewritten—not because the science changed, but because now the audience is the factory, not the lab.

In invasive neurotech, manufacturing isn’t a department. It’s a second act. And most startups need to prepare for it.

Most neurotech companies will think their product is the implant. It’s not. Or at least not the whole product. The real product is the entire procedure—from patient onboarding to surgical setup to long-term data management.

If your implant works, but it takes six hours to install and requires a robotic arm operated by someone with a PhD in your company’s SDK, you don’t have a product.

The surgeon, not the patient, is the critical user in scaling. Can they learn the procedure quickly? Can they perform it without on-site support? Does the hardware slot into the existing surgical workflow, or does it require a bespoke OR configuration? Does the interface make sense during a time-sensitive operation?

These questions matter more than your decoding accuracy.

Neuralink is trying to own this entire stack by building their own surgical robot. It’s an ambitious play, and it might work—but most companies can’t afford to do the same. For everyone else, the path to scale runs through ease of use, intuitive tools, and minimal training overhead.

Because if the average neurosurgeon won’t use it, you’re not ready to scale.

A successful implant with no reimbursement is a failed product.

Startups tend to treat reimbursement as something to figure out after FDA clearance. But in medtech, the payer landscape is part of the product. If your device isn’t covered by insurance, hospitals won’t adopt it. Period.

Reimbursement isn’t just about proving efficacy. It’s about proving that your device is more valuable, clinically and economically, than the standard of care. That means defining clear patient outcomes, designing trials that produce the right endpoints, and building an ironclad health economics case.

Without a CPT code or a reimbursement pathway, even a life-changing device will collect dust. And if your target indication is niche or difficult to quantify, the burden is even higher.

Companies that treat reimbursement as a regulatory formality will lose to companies that treat it as a core strategic function from day one.

Invasive neurotech is not a consumer product. You’re not selling headphones. You’re placing a device in someone’s skull and telling them it will work for years. That’s not just a technical promise—it’s a moral one.

How will your device age? Will the signal degrade? What happens if the company folds? Who maintains the hardware, updates the software, or handles explants?

Patients can’t uninstall your product. They can’t reset it. They can’t call AppleCare. If your company disappears, they’re stuck with a piece of metal and plastic in their heads.

This isn’t theoretical. It has already happened in the cochlear implant industry, where legacy devices became unsupported. It’s a looming threat in neurotech.

Companies must design for maintainability, durability, and organizational continuity. That includes things like backwards-compatible firmware, robust external components, and partnerships with institutions that can provide long-term service even if the original company is gone.

If you can’t guarantee your product’s lifespan, you shouldn’t be implanting it.

The final challenge in scaling invasive neurotech isn’t technical at all. It’s emotional.

You are asking people to let you open their skull and place a device in their brain. That requires trust—deep, sustained, and earned trust. Trust in your product. Trust in your company. Trust in your ethics, your roadmap, your commitment to safety.

That means you can’t treat consent as a checkbox. You can’t treat users as datasets. You can’t cut corners on data privacy or interface design. You can’t disappear from a patient’s life once the procedure is done.

As you scale, you need to scale your ability to listen, support, and protect. You need patient portals that explain data clearly. Clinical staff that can answer real questions. Engineers who think about user agency, not just latency.

Because if people don’t trust you, they won’t let you in. And once you’re in, if you break that trust, there’s no coming back.

The invasive neurotech boom is coming. Money is pouring in. Talent is moving fast. Demos are dazzling. But scaling this technology will require more than signal decoding and surgical robots.

It will require companies to evolve from research labs into fully-fledged medical device organizations. It will require engineering discipline, surgical empathy, manufacturing excellence, regulatory foresight, and business model clarity. It will require responsibility—not just for what the product does, but for what it means to put that product in someone’s head.

The winners in this space won’t be the ones who just build the best implant.

They’ll be the ones who understand what it means to scale a brain-machine interface as if it’s a life-long partnership.

Because that’s what it is.

Until next time,

—Daniel