The moment we built for

There was a long period when much of Silicon Valley treated government as something to avoid.

The best founders wanted to build products that moved at software speed. The best investors wanted markets that scaled without procurement cycles, compliance burdens, or the slow machinery of Washington. For a generation of venture capital, the government was often viewed as too complex, too slow, and too far removed from the center of innovation.

That was always a strange break from history.

Semiconductors, GPS, and the internet were not born in isolation from the state. They emerged from a deep relationship between entrepreneurs, researchers, capital, and the U.S. government. The foundations of the modern technology economy were built through that bridge. Over time, the bridge eroded.

Harpoon Ventures was founded in 2018 because we believed it would need to be rebuilt.

Today, that belief is no longer contrarian. The world has moved toward it.

We are proud to announce the final close of Harpoon Ventures Fund IV, an oversubscribed $155 million fund dedicated to backing founders building critical technologies for America and its allies. With Fund IV, Harpoon now manages more than $450 million in assets and has greater capacity to support the founders building into the most important technology markets of this era.

This is not simply a new fund for us. It is the continuation of the work Harpoon was built to do.

The world moved toward the thesis

The last decade ended the illusion that technology could be separated from national power.

AI turned compute into strategic infrastructure. Compute exposed power as a bottleneck. Power put nuclear and grid resilience back at the center of the national conversation. War in Ukraine showed how quickly the battlefield can be rewritten by drones, autonomy, software, sensors, and low-cost manufacturing. Supply chain shocks forced the United States and its allies to confront how much industrial capacity had been allowed to move offshore. Cyberattacks made clear that digital infrastructure is physical infrastructure. Biotechnology became not only a healthcare market, but a biosecurity imperative.

These are not separate stories. They are the same story moving through different domains.

The next generation of global power will be shaped by who can build, manufacture, secure, and deploy the technologies that matter most. That work will not be done by governments alone. It will be done by founders.

At the same time, government has changed its posture toward technology. The federal government is no longer only a regulator, grant-maker, or distant customer for a small number of defense primes. Across defense, energy, manufacturing, AI, cybersecurity, and biotechnology, public capital and procurement are moving toward frontier technology companies with a level of urgency we have not seen in decades.

That shift matters because government markets are enormous, but they are not easy. For founders, the path from breakthrough technology to government adoption remains difficult, fragmented, and opaque. For investors, it is not enough to believe in a market from the outside. You have to know how the market actually works.

That is the gap Harpoon was built to close.

The bridge had to be rebuilt

From the beginning, our conviction was simple: the founders building the most important companies of the next era would need to move across both commercial and government markets.

They would need venture capital that understood technical risk and market risk. They would also need help navigating procurement, program offices, non-dilutive funding, strategic partnerships, and the long path from early adoption to scaled deployment.

Harpoon chose to build that capability before it was obvious.

We spent years building relationships across the government ecosystem, learning the pathways that matter, and developing the operating experience to help founders move through them. We have worked across SBIRs, OTAs, direct program relationships, defense customers, energy programs, and other parts of the federal market that can determine whether a critical technology company remains a promising startup or becomes a generational business.

That work is not theoretical. Harpoon has helped portfolio companies secure more than $1 billion in government funding, revenue, and program awards.

We laid down this groundwork because we deeply understood the government’s potential as a growth engine for founders building technologies of consequence.

The Freedom Stack

We call the set of markets we invest behind the Freedom Stack.

It includes compute sovereignty and AI, energy and materials, IT and cybersecurity, next-generation aerospace and defense, advanced manufacturing and robotics, and biotechnology and biosecurity. These markets are the foundational layers of technological and industrial power.

They are also increasingly connected.

AI is not just a software story. It is a compute story, an energy story, a semiconductor story, and a national infrastructure story. Defense is not just a hardware story. It is an autonomy, manufacturing, communications, and software story. Energy is not just a climate story. It is a resilience, industrial capacity, and AI infrastructure story.

The strongest companies of the next decade will not fit neatly inside old sector boundaries. They will be defined by the bottlenecks where technical advantage matters most.

Harpoon has been investing there across prior funds, often before policy, capital, and public attention caught up.

Investing before consensus

Cybersecurity was an early piece of our strategy. We believed that as software moved deeper into the economy, the most valuable security problems would keep migrating to the newest layers of the stack, and that the teams who got there first would define the category. That took us to Robust Intelligence, founded to secure AI systems against a threat most of the market had not yet reckoned with: that the models themselves could be attacked or manipulated. We backed the team well ahead of the attention AI security now commands, and the conviction was validated quickly by an early acquisition.

n8n is another example. At the time, much of the market still saw automation as a workflow problem. We saw the early signs of something larger: as AI became more capable, software would begin to automate more of the work that sits between systems, people, and data.

That pattern has only accelerated. More capable AI creates more automation. More automation creates more demand for compute. More compute creates more pressure on power, chips, and infrastructure. The bottlenecks compound.

That conviction also led us to MatX, founded by the engineers who helped build the software and silicon behind Google’s TPUs. MatX is building processors purpose-built for large language model workloads, attacking one of the defining infrastructure problems of the AI era. If AI is going to reshape the economy, the physical and computational stack beneath it has to be rebuilt as well.

Energy follows the same logic. Nuclear was out of favor for a long time, despite being one of the clearest answers to the power requirements of a more electrified, AI-driven economy. We backed Aalo Atomics at the Series A before the federal nuclear push. The company brought a manufacturing-first mindset to advanced nuclear, with a team deeply rooted in reactor design and national lab experience.

Since then, the federal government has moved aggressively to accelerate advanced reactor development. Aalo is exactly the kind of company we believe this moment demands: technically ambitious, operationally fast, and aligned with a market that has moved from theoretical need to national priority.

Harpoon’s role was not only to invest. It was to help the team navigate the government pathways and relationships that could accelerate its progress. That is the model we have worked to build across the portfolio: capital, conviction, and operating help where the commercial and government worlds meet.

In aerospace and defense, the lesson has been equally clear. The modern battlefield is changing faster than legacy systems can adapt. Ukraine made that reality visible to the world, but many of the people closest to the fight saw it earlier. Low-cost drones, autonomy, counter-UAS systems, and software-defined capabilities are reshaping how militaries think about speed, cost, and scale.

Harpoon’s roots in the operator community gave us direct insight into that shift. We backed founders building for the battlefield that exists now, not the one procurement systems were designed around a decade ago. When we saw a gap no existing company was filling, we did not wait for one to appear. We incubated Vector to mass produce drones and train the Warfighter on the next foundational layer of the battlefield. Our conviction also helped shape investments across counter-UAS and air defense, including a stealth surface-to-air startup building a new class of interceptor missiles purpose-built to knock down drones at a fraction of the cost of the legacy systems and Alta Ares where allied demand is accelerating as Europe and the United States confront the need to rebuild defense capacity for a new era. 

Advanced manufacturing is another part of the same story. Few problems reveal the state of the American industrial base more clearly than shipbuilding. The United States once built at a scale the world could not match. Today, rebuilding domestic maritime capacity has become a national priority. The problem will not be solved by capital alone, and it will not be solved by legacy processes alone. It will require founders applying automation, software, robotics, and modern manufacturing to industries that have barely changed in decades.

That is where we want to invest.

Across the Freedom Stack, our pattern is consistent. We look for founders building into technical bottlenecks before they become obvious. We back them early. We help them move through markets that are difficult but enormous. And we stay focused on the categories where commercial demand and national need are becoming impossible to separate.

Why Fund IV, why now

The opportunity in front of us is not a normal venture cycle.

In normal cycles, capital chases growth. In this one, capital is chasing capability. The implication of that difference is significant. The companies that matter in today’s environment will not only build large markets; they will determine whether the United States and its allies remain competitive in a fractured world, and whether democratic values and order persist. 

That is a different kind of venture opportunity.

It is also a narrow window. Government demand is rising. Policy is moving. Private capital is waking up. Founders are leaving the obvious problems behind and choosing to build in markets that were once considered too hard, too regulated, or too tied to government. Categories are forming now. The companies that become leaders in these markets will likely be set in motion during this period.

We believe the next generation of critical technology companies will be built by founders who can move with speed, technical depth, and a sense of national purpose. They will need investors who understand the commercial markets they are building into and the government pathways that can accelerate them. They will need partners who can help them earn trust with customers that matter, without slowing them down.

That is the firm we have spent the last eight years building.

Fund IV gives us more capacity to do the work at greater scale: backing founders earlier, helping them navigate government and commercial adoption, and supporting companies building the technologies that will define the next era of American and allied leadership.

The moment we built for has arrived.

The founders are already building.

So are we.