Valuations by round
Announced	Stage	Valuation	Basis
Jan 24, 2020	Seed	$12.5M	Post-money
Feb 1, 2021	Series A	$50.5M	Post-money
Nov 2, 2021	Series B	$181M	Post-money
Aug 8, 2023	Series C	$317M	Post-money
Jun 10, 2025	Series D	$650M	Basis not stated
Aug 3, 2026	Series E+	$2.00B	Basis not stated

Funding rounds
Announced	Stage	Amount	Valuation	Lead investors	Other investors	Confidence
Aug 3, 2026	Series E+	$250M	$2.00B?	New Enterprise Associates, NightDragon	Craft Ventures, Prosperity7 Ventures, Qualcomm Ventures, Sapphire Ventures, SignalFire	Reported
Jan 13, 2026	Undisclosed	Undisclosed	—	Prosperity7 Ventures	—	Confirmed
Jun 10, 2025	Series D	$100M	$650M?	New Enterprise Associates	9Yards Capital, Craft Ventures, Qualcomm Ventures, SignalFire	Confirmed
Aug 8, 2023	Series C	$40.0M	$317M	Craft Ventures	SignalFire	Confirmed
Nov 2, 2021	Series B	$30.0M	$181M	SignalFire	—	Confirmed
Feb 1, 2021	Series A	~$5.0M	$50.5M	SignalFire	—	Speculative
Jan 24, 2020	Seed	~$2.5M	$12.5M	SignalFire	—	Speculative

Series E+
Led by New Enterprise Associates, NightDragon
With Craft Ventures, Prosperity7 Ventures, Qualcomm Ventures, Sapphire Ventures, SignalFire
Valuation $2.00B?
$250M
Aug 3, 2026
Undisclosed
Led by Prosperity7 Ventures
Confirmed
Undisclosed
Jan 13, 2026
Series D
Led by New Enterprise Associates
With 9Yards Capital, Craft Ventures, Qualcomm Ventures, SignalFire
Valuation $650M?
Confirmed
$100M
Jun 10, 2025
Series C
Led by Craft Ventures
With SignalFire
Valuation $317M
Confirmed
$40.0M
Aug 8, 2023
Series B
Led by SignalFire
Valuation $181M
Confirmed
$30.0M
Nov 2, 2021
Series A
Led by SignalFire
Valuation $50.5M
Speculative
~$5.0M
Feb 1, 2021
Seed
Led by SignalFire
Valuation $12.5M
Speculative
~$2.5M
Jan 24, 2020

Totals add known amounts using recorded USD conversions where available; other currencies are shown separately. A ~ marks an estimated amount.

Sources15

Profile5

1
DatabaseHorizon3.ai - PitchBook company profile
PitchBook · Supports Organization · employee range, Organization · founded year, Organization · linkedin url, Organization · x url
“employee_range: 501-1000 (profile: 550)”
2
DatabaseSixth-Domain public startup directory
Sixth-Domain · Supports Organization · country, Organization · kind
“{"country": "USA", "hq_iso2": "US", "id": "280c9b9c-8089-43ca-ad3b-7ef7e9c8cdcd"}”
3
DatabaseHorizon3.ai - Crunchbase company profile
Crunchbase · Supports Organization · hq city, Organization · linkedin url, Organization · x url
“hq_city: San Francisco”
4
DatabaseHorizon3.ai - LinkedIn company profile
LinkedIn · Supports Organization · employee range, Organization · founded year, Organization · hq city, Organization · linkedin url
“employee_range: 501-1000 (profile: 501-1,000 employees)”
5
DatabaseHorizon3.ai - Owler company profile
Owler · Supports Organization · founded year, Organization · hq city, Organization · linkedin url, Organization · x url
“founded_year: 2019”

Products1

6
CompanyHome | Horizon3.ai
Horizon3.ai · Supports Organization · description, Organization · name, Organization · website, System
“Horizon3 uses real-world attacks to safely show what attackers can actually do in your environment—so you can fix and prove what matters.”

Funding9

7
NewsHorizon3 triples valuation with $250m raise for AI security
FinTech Global · Aug 4, 2026 · Supports Funding round · post money valuation usd
“the $650m it commanded at Series D”
8
NewsHorizon3 hits $2 billion valuation with $250M Series E as AI threats escalate
TechCrunch · Aug 3, 2026 · Supports Funding round · post money valuation usd
“raised a $250 million Series E at a $2 billion valuation”
9
NewsCybersecurity firm Horizon3 crosses $2 billion valuation in new funding round
Reuters · Aug 3, 2026 · Supports Funding round · amount
“it has raised $250 million in its latest funding round”
10
CompanyHorizon3.ai Secures Investment from Prosperity7 Ventures to Protect AI Datacenters and Critical Infrastructure
Business Wire · Jan 13, 2026 · Supports Funding round
“today announced an investment from Prosperity7 Ventures”
11
CompanyHorizon3.ai Raises $100M to Cement Leadership in Autonomous Security
Business Wire · Jun 10, 2025 · Supports Funding round · amount
“today announced a $100 million Series D funding round led by NEA”
12
CompanyHorizon3.ai Raises $40M Series C to Confront Attackers with Proactive, Continuous Security Testing
Business Wire · Aug 8, 2023 · Supports Funding round · amount
“announced $40M in Series C funding led by Craft Ventures with participation from Signal Fire”
13
CompanyHorizon3.ai Raises $30M Series B to Disrupt the Pentesting Market
PR Newswire · Nov 2, 2021 · Supports Funding round · amount
“Horizon3.ai Raises $30M Series B to Disrupt the Pentesting Market”
14
DatabaseHorizon3.ai - Forge company profile
Forge Global · Supports Funding round · amount, Funding round · post money valuation usd
“01/24/2020 Series Seed $2.5M $0.24 $12.5M”
15
NewsFenwick Represents Horizon3.ai in $30M Series B Financing
Fenwick · Supports Funding round
“The financing round was led by SignalFire”

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