What are the top AI trust, risk and security startups by total funding raised?

Top startups in the AI TRiSM market ranked by total funding raised

Here is the current ranking of the AI TRiSM startups that raised the most, with the total each one has raised and our confidence level.

If you want to go deeper into the AI TRiSM startup landscape, check our report covering the AI TRiSM market.

1. Minimum: known rounds total $36M versus $44.5M reported in total.

Is Arena clearly the best-funded AI TRiSM startup?

Yes. Arena is clearly the best-funded AI TRiSM startup, with $450M raised, 1.9x the total of Alice in second place.

Arena reached that position with only 3 equity rounds. Its October 2026 Series B was $200M, the largest single round of any AI TRiSM startup, and came after a $100M seed round in May 2025 and a $150M Series A in January 2026. The company uses that capital to build independent evaluation infrastructure for frontier models and AI agents, including the Arena Alignment Index launched alongside the Series B.

Only 10 startups have raised at least $100M, so Arena has pulled away from most of the market. It can spend on research, data, infrastructure and distribution while many competitors are still working through early rounds.

Did Arena get to the top with one giant round?

No. Arena got to the top of AI TRiSM funding through three large rounds in quick succession, not one giant check.

The October 2026 Series B is the biggest of the three, and Arena's seed round in May 2025 was already the largest AI TRiSM round of that year. Investors kept increasing the size of their commitment as independent model and agent evaluation became more important to labs, developers and enterprises.

Arena was founded in 2025, so the speed is unusual. It reached the top with very few financings rather than slowly accumulating capital over a decade. Some AI infrastructure companies can now move from early funding to very large institutional rounds quickly when investors think they sit in a strategic layer.

Is Alice the closest fundraising challenger to Arena?

Yes. Alice is the closest fundraising challenger to Arena, with $240M raised across 2 rounds.

Alice's most recent financing was a $140M round in August 2026. Bloomberg reported that the company works on protecting AI models from misuse and rogue behavior and that the round was led by Apax Digital with participation from SentinelOne and Samsung. Alice has built its total in only two disclosed equity rounds.

Arena still remains well ahead at 1.9x Alice's total. The comparison shows two expensive parts of AI TRiSM: independent evaluation on one side and deep AI safety and security on the other. Alice's funding says investors are willing to pay heavily for the security build-out before the market has fully matured.

Why has Zenity raised so much for AI agent security?

Zenity has raised $184M because investors see AI agent security as a new enterprise control layer, not a small add-on to existing cybersecurity.

The company sits third in total funding and raised a $125M Series C in August 2026 led by Norwest. Zenity says its platform is purpose-built for AI agents that work across finance, customer service, engineering, HR and other business workflows.

Autonomous agents create machine identities, access company data, call tools and execute actions. That forces security teams to handle discovery, policy, monitoring and intervention across a new class of software actor. Zenity now has enough capital to build product depth and global distribution before the category settles around a few large vendors.

How much has HiddenLayer raised for AI security?

HiddenLayer has raised $156M for AI model and agent security, side by side with Onyx Security at $153M among the most heavily funded AI TRiSM companies.

HiddenLayer's September 2026 Series B was $100M and focused on securing generative, predictive and agentic AI, including runtime protection for coding agents. Onyx Security raised a $113M Series B in July 2026 and said revenue had grown fourfold in the four months since it emerged from stealth.

The similar totals hide different approaches. HiddenLayer covers a wider model-to-agent security surface, while Onyx focuses heavily on visibility, governance and runtime control for autonomous systems. Investors are still backing several architectures rather than choosing one clear winner.

How concentrated is AI TRiSM funding at the top?

AI TRiSM funding is highly concentrated by company count: only 10 of 192 startups have raised at least $100M.

Those ten include Arena, Alice, Zenity, HiddenLayer, Onyx Security, Noma Security, Arize AI, Braintrust, Protect AI and Neo Security. The remaining 182 companies, or 95% of the total, are below $100M.

That leaves a broad base of early companies and a very narrow group with enough capital to build large sales teams, deep research and enterprise integrations. The middle can be uncomfortable: startups there face heavily funded platforms above them and newer companies below them that can still move faster.

The table below shows the ten AI TRiSM startups with the largest total equity funding.

Company	Total raised	Last round	Stage
Arena	$450M	$200M	Series B
Alice	$240M	$140M	undisclosed stage
Zenity	$184M	$125M	Series C
HiddenLayer	$156M	$100M	Series B
Onyx Security	$153M	$113M	Series B
Noma Security	$132M+	$100M	Series B
Arize AI	$131M	$70M	Series C
Braintrust	$124M	$80M	Series B
Protect AI	$108M	$60M	Series B
Neo Security	$100M+	$75M+	Growth Equity

"+" means at least: some round amounts were not disclosed.

Is Noma Security still one of the best-funded AI security startups?

Yes. Noma Security remains one of the best-funded AI security startups, with at least $132M raised.

Its July 2025 Series B was $100M and was led by Evolution Equity Partners. Noma said ARR had increased more than 1,300% over the prior year and that it had customers across financial services, life sciences, retail and big technology. The company secures AI applications and agents across their lifecycle.

Noma still ranks sixth even though several companies around it raised large rounds more recently. That suggests it reached the scale-up phase earlier than many agent-security peers. Staying near the top will now depend less on old fundraising momentum and more on whether the business keeps converting that early lead into commercial scale.

How much did Arize AI and Protect AI raise before being bought?

Arize AI raised $131M and Protect AI $108M before larger companies bought them, enough to keep both among the ten best-funded AI TRiSM startups.

Arize's largest financing was a $70M Series C in February 2025, when it described evaluation and observability as infrastructure for reliable AI agents, and Dynatrace completed its purchase of the company in October 2026. Protect AI raised a $60M Series B in August 2024 and was later acquired by Palo Alto Networks, which integrated its capabilities into Prisma AIRS.

Those totals still tell us how much capital it took to build products that strategic buyers wanted. Palo Alto Networks explicitly connected Protect AI to model scanning, posture management, red teaming, runtime protection and agent security, so this was not a peripheral capability being folded into a larger platform.

Is Braintrust unusually well funded for an AI evaluation company?

Yes. Braintrust is unusually well funded for an AI evaluation company, with $124M raised across 4 rounds.

Its February 2026 Series B was $80M, led by ICONIQ. Braintrust describes its product as an observability layer for production AI and puts evaluation inside the full development and deployment workflow rather than treating it as a one-time audit.

That puts Braintrust eighth overall, ahead of many security and governance companies. Investors are clearly willing to fund evaluation as software infrastructure when it becomes part of how teams ship and monitor production AI every day.

Is Neo Security's $100M launch unusual even for AI security?

Neo Security's launch is unusual even for AI security, because the company came out of stealth with at least $100M of equity already raised.

Neo launched in July 2026 with funding from Andreessen Horowitz and Bessemer Venture Partners, plus Craft Ventures and Merlin Ventures. The company positions itself as a real-time control layer for agentic software, covering AI agents, AI-enabled applications, browsers, identities and traditional software gaining autonomous capabilities. Neo Security's most recent round, in July 2026, was a Growth Equity round of at least $75M.

Most AI TRiSM companies start with one modest seed round. Neo arrived with enough capital to build at a much larger scale from day one. That reduces financing risk but raises the bar for execution because a company funded like a later-stage platform has to prove product-market fit quickly.

Are most AI TRiSM startups still one-round companies?

Yes. Most AI TRiSM startups are still one-round companies: 116 of the 192 we track have raised only a single equity round.

That figure keeps the market's maturity in perspective. The top ten have raised nine-figure sums, but the median total is at least $8M and most companies have not yet returned for a second priced financing.

The category expanded quickly around AI agents, enterprise generative AI and model governance. The next test is simple: which companies can win enough enterprise adoption to raise again. Many others will be acquired, pivot, stay small or disappear.

Which AI TRiSM startup has raised through the most rounds?

Fiddler AI has raised more equity rounds than any other AI TRiSM startup, with 6.

Founded in 2018, Fiddler has had more time than most agent-security startups to move from model monitoring into broader AI observability, governance and security. Its January 2026 Series C was $30M, and the company said revenue had grown more than 4x over the previous 18 months while it developed a control plane for compound AI systems.

A long funding history is not automatically better. Arena reached the top in only 3 rounds, while Neo reached at least $100M in 2. Fiddler simply shows the older path through this market: raise repeatedly, expand the product as AI changes, then attract a larger security platform. CrowdStrike announced in November 2026 that it plans to acquire Fiddler; until the deal closes, our ranking still shows Fiddler as an independent startup.

Is the money in AI TRiSM mostly going to American startups?

Mostly, yes, but Israel punches far above its weight in AI TRiSM: Alice, Zenity, Onyx Security and Noma Security are all Israeli, and all four sit in the top six by total funding.

The other leaders, from Arena and HiddenLayer to Braintrust, Arize AI, Protect AI and Neo Security, are American. Outside these two countries, the best-funded startup is Mindgard from the United Kingdom, ranked 28th.

The US combines frontier-model research, the largest enterprise software market and deep venture pools. Israel brings a dense cybersecurity ecosystem that maps naturally onto agent identity, runtime control and AI security. Across 20 countries, those two ecosystems currently stand out most clearly.

Are $100M rounds becoming normal for AI TRiSM startups?

No. $100M rounds are still exceptional in AI TRiSM even though several have happened lately.

The largest single AI TRiSM round is Arena's $200M Series B in October 2026. The largest round in 2025 was Arena's $100M seed round, while Protect AI had the largest round in 2024 at $60M and HiddenLayer led 2023 at $50M. In 2026, other very large financings included Alice at $140M, Zenity at $125M, Onyx Security at $113M and HiddenLayer at $100M.

That is a higher ceiling, not a new normal. Only 10 companies have raised at least $100M in total, and most startups still have one round. Nine-figure rounds remain concentrated around companies that investors think can own an important layer in evaluation, agent security or runtime control.

Are investors funding AI agent security more aggressively than governance software?

Yes. At the top of AI TRiSM, investors are putting much more money into agent security than into standalone governance software.

Zenity has raised $184M, HiddenLayer $156M, Onyx Security $153M and Noma Security at least $132M. Straiker has raised $85M after a $64M Series A in June 2026, and WitnessAI has raised $86M. Governance-focused Credo AI sits lower, with at least $39M, while many policy and compliance vendors remain in the single-digit or low-double-digit millions.

The reason is practical. Agent security protects systems that can execute actions, reach company data and interact with production infrastructure. Governance still matters, especially in regulated sectors, but spending often moves faster when the risk is active and operational. The product categories are also blending together as security vendors add discovery, policy and auditability.

Does AI evaluation still attract serious funding beside security?

It does. AI evaluation still attracts serious funding beside security, with Arena, Braintrust, Arize AI and Patronus AI all raising substantial capital.

Arena leads the entire market, and Arize AI and Braintrust both sit in the top ten. Patronus AI has raised $70M, and its June 2026 Series B of $50M pays for Digital World Models that predict how agents behave over very long workflows. Braintrust's February 2026 Series B was $80M, while Arize AI raised $70M in February 2025 for evaluation and observability infrastructure.

Testing becomes more valuable as AI applications become less deterministic and agents run longer workflows. Evaluation then moves into development, deployment and continuous monitoring. Security has more companies near the top, but evaluation has produced the single best-funded startup in the market.

How fresh is the capital behind the leading AI TRiSM companies?

The capital behind the leading AI TRiSM companies is very fresh: Arena, Alice, Zenity, HiddenLayer, Onyx Security, Braintrust and Neo Security all had their last round in 2026.

The whole market looks the same. 86 startups had their last round in 2026, compared with 57 in 2025, 39 in 2024, 6 in 2023 and only 4 before 2023.

The point is simple: investors are still actively backing the category. Security teams have not settled on one standard AI control stack yet, so vendors still have room to define how agent security, runtime controls and continuous evaluation should work.

Will most AI TRiSM startups end up being bought by bigger companies?

Not most so far, but plenty: 17 of the 192 AI TRiSM startups we track have already been acquired.

Buyers are going after the leaders too. Protect AI and Arize AI, two of the ten best-funded, now belong to Palo Alto Networks and Dynatrace, and CrowdStrike announced in November 2026 that it plans to buy Fiddler AI.

AI TRiSM may not produce dozens of independent public companies. Some startups will become large platforms, while others will become modules inside cybersecurity, cloud or enterprise software suites. Funding history still helps show which acquired companies were substantial venture-backed businesses rather than small acqui-hires.

So, which AI trust, risk and security startups have raised the most money?

Arena is the number one AI TRiSM startup by total equity raised, with $450M, followed by Alice at $240M and Zenity at $184M.

HiddenLayer has raised $156M, Onyx Security $153M, Noma Security at least $132M, Arize AI $131M, Braintrust $124M, Protect AI $108M and Neo Security at least $100M. Some are independent leaders and others have already been acquired, but all show how much capital can go into building a major AI control layer.

The market is splitting into two groups. A small set of companies can raise nine-figure totals, while most remain early. Agent security takes much of the biggest capital, but evaluation still matters at the very top because Arena leads the whole market.

The table below shows what we found.

Question	Answer
Is there a clear AI TRiSM funding leader?	Yes, Arena is far ahead of every other AI TRiSM startup. It has raised $450M across only 3 equity rounds. No other startup in this market comes close to that total.
How fast did Arena build its lead?	Very fast, since its first round came only in May 2025. A $100M seed and a $150M Series A came first. The October 2026 Series B then pushed it far ahead.
Is Arena's lead safe from Alice?	For now, yes, because Alice remains a distant second. Alice has raised $240M in only two disclosed rounds. Its August 2026 round, led by Apax Digital, was its biggest.
Is agent security attracting the biggest checks?	Yes, agent security holds most places near the top. Zenity, HiddenLayer, Onyx Security and Noma Security each exceed $100M. Governance software raises far smaller amounts so far.
Is AI TRiSM funding broadly late-stage?	No, only a thin layer of startups is well funded. Just 10 of the 192 startups have raised at least $100M. Most of the market is still raising its first rounds.
Do most startups ever raise a second round?	Not yet, most are still one-round companies. 116 of the 192 startups have only one equity round. Winning a follow-on round is the next big test.
Which company has raised most often?	Fiddler AI has raised more rounds than any rival. Founded in 2018, it has closed 6 equity rounds. CrowdStrike announced plans to buy it in November 2026.
Where do the best-funded startups come from?	Mostly the United States, with Israel close behind. Alice, Zenity, Onyx Security and Noma Security sit in the top six. Israel's cybersecurity base maps neatly onto AI agent security.
Are $100M rounds normal now?	No, nine-figure rounds are still the exception in this market. The biggest so far is Arena's October 2026 Series B. Most startups have raised far smaller amounts in total.
Can an evaluation company lead AI TRiSM?	Yes, evaluation has already produced the best-funded startup here. Arena independently tests frontier models and AI agents. Braintrust and Arize AI also sit in the top ten.
Who is buying AI security startups?	Large security and software platforms are doing the buying. Palo Alto Networks bought Protect AI, and Dynatrace bought Arize AI. Specialist AI security is turning into a module of bigger suites.