Abnormal AI
Company History
Abnormal AI History: Founding, Growth & Key Milestones
Founded 2018 in San Francisco, California
When was Abnormal AI founded?
Abnormal AI was founded in 2018 in San Francisco, California by Evan Reiser and Sanjay Jeyakumar, making it 8 years old.
- Founded
- 2018
- Founding place
- San Francisco, California
- Founders
- Evan Reiser and Sanjay Jeyakumar
- Headquarters today
- Las Vegas, Nevada, United States
- Milestones documented
- 15 (2018–2026)
- Current CEO
- Evan Reiser
| Year | Event |
|---|---|
| 2018 | Abnormal Founded |
| 2019 | Launch With $24M Series A |
| 2020 | $50M Series B Led by Menlo Ventures |
| 2022 | $210M Series C at $4B Valuation |
| 2023 | ARR Passes $100M |
| 2024 | $250M Series D at $5.1B Valuation |
| 2025 | Rebrand to Abnormal AI |
| 2025 | FedRAMP Moderate Authorization |
| 2025 | AI Agents and Germany Expansion |
| 2026 | Attune 1.0 Behavioral Model |
| 2026 | Anthropic Logo Lawsuit |
| 2026 | Identity and AI Security Products |
| 2026 | OpenAI Partnership |
| 2026 | SoftBank Resells Abnormal in Japan |
| 2026 | AI Security Suite |
- Where was Abnormal AI founded?
- Abnormal AI was founded in San Francisco, California in 2018.
- Who founded Abnormal AI?
- Abnormal AI was founded by Evan Reiser and Sanjay Jeyakumar.
- When did Abnormal AI start?
- Abnormal AI was founded in 2018.
- How old is Abnormal AI?
- Abnormal AI is 8 years old as of 2026.
Founding Story
Evan Reiser and Sanjay Jeyakumar worked together on machine learning systems at TellApart and Twitter; Reiser had co-founded AdStack, which TellApart acquired, and Jeyakumar was a founding engineer at TellApart before it was bought by Twitter. They started the company in late 2018, incubated at Greylock's offices, under the name Abnormal AI. They soon renamed it Abnormal Security because, Reiser later wrote, the market did not yet take AI-named security companies seriously. It came out of stealth in November 2019 with a $24 million Series A led by Greylock.
Founders
Evan Reiser
Evan Reiser co-founded Abnormal in 2018 and has led it as CEO from its launch through its 2024 Series D at a $5.1 billion valuation and the 2025 rebrand to Abnormal AI. Before Abnormal he led product management and machine learning teams for Twitter's advertising business. He co-founded Bloomspot, which JPMorgan Chase acquired, and AdStack, which TellApart acquired. (Exact birth year remains publicly undisclosed).
Sanjay Jeyakumar
Sanjay Jeyakumar co-founded Abnormal in 2018 and was its CTO when the company launched in 2019. Before Abnormal he was the systems architect at Twitter responsible for the distributed data processing and machine learning systems behind Twitter's business. (Exact birth year remains publicly undisclosed).
Key Milestones
Abnormal Founded
Evan Reiser and Sanjay Jeyakumar start the company in late 2018, incubated at Greylock's offices, under the name Abnormal AI; it soon becomes Abnormal Security.
Source: greylock.comLaunch With $24M Series A
Abnormal Security comes out of stealth in November 2019 with a $24 million Series A led by Greylock.
Source: abnormalsecurity.com$50M Series B Led by Menlo Ventures
Abnormal raises a $50 million Series B led by Menlo Ventures in November 2020 after tripling ARR during the year; Forbes reported a valuation above $500 million.
Source: businesswire.com$210M Series C at $4B Valuation
Insight Partners leads a $210 million Series C in May 2022 at a $4 billion valuation, after Abnormal tripled ARR and doubled headcount in 2021.
Source: businesswire.comARR Passes $100M
Abnormal says in August 2023 that ARR has passed $100 million and hires former Forescout CEO Michael DeCesare as president.
Source: tech.yahoo.com$250M Series D at $5.1B Valuation
Wellington Management leads a $250 million Series D in August 2024 at a $5.1 billion valuation; ARR has passed $200 million and customers exceed 2,400.
Source: abnormal.aiRebrand to Abnormal AI
In April 2025 the company returns to its original name, Abnormal AI, and changes its legal name to Abnormal AI, Inc.
Source: abnormal.aiFedRAMP Moderate Authorization
Abnormal achieves FedRAMP Moderate authorization in April 2025, followed by GovRAMP Moderate authorization in September 2025.
Source: businesswire.comAI Agents and Germany Expansion
Abnormal launches AI Phishing Coach and AI Data Analyst agents in April 2025 and expands operations into Germany.
Source: abnormal.aiAttune 1.0 Behavioral Model
Abnormal reports more than 4,500 customers, including over 25% of the Fortune 500, and the launch of Attune 1.0, a behavioral foundation model.
Source: abnormal.aiAnthropic Logo Lawsuit
Anthropic sues Abnormal in July 2026, alleging its 2025 logo copies Anthropic's branding.
Source: axios.comIdentity and AI Security Products
In July 2026 Abnormal launches Identity Threat Protection, AI Governance and Infiltration Prevention.
Source: abnormal.aiOpenAI Partnership
Abnormal and OpenAI announce a partnership in August 2026; Abnormal joins OpenAI's Daybreak cyber partner program.
Source: businesswire.comSoftBank Resells Abnormal in Japan
SoftBank Corp. begins offering Abnormal's email security platform to enterprise customers in Japan in September 2026.
Source: businesswire.comAI Security Suite
In September 2026 Abnormal adds AI Employee Guardrails, AI Agent Security and AI Security Workbench, saying it protects 30% of the Fortune 500.
Source: finance.yahoo.comKeep researching Abnormal AI
Abnormal AI Company History FAQ
What are Abnormal Security's key milestones?
Founded in 2018; $24M Series A in 2019; $50M Series B in 2020; $210M Series C at $4B in 2022; $100M ARR in 2023; $250M Series D at $5.1B in 2024; rebrand to Abnormal AI and FedRAMP Moderate in 2025; identity and AI security products in 2026.
How fast did Abnormal's ARR grow?
Abnormal reported a 3x ARR increase in 2020 and a tripling in 2021, then passed $100 million in August 2023 and $200 million in August 2024.
Why did Abnormal Security change its name to Abnormal AI?
Abnormal AI was the original 2018 name. The company switched to Abnormal Security because buyers did not take AI-named security firms seriously, then returned to Abnormal AI in April 2025 as it expanded beyond email.
When did Abnormal get FedRAMP authorization?
Abnormal achieved FedRAMP Moderate authorization in April 2025 and GovRAMP Moderate authorization in September 2025. In August 2026 it said it was pursuing FedRAMP High.
When did Abnormal expand internationally?
Abnormal expanded into Europe, Asia and Australia by 2024, added operations in Germany in 2025 and has operated in Japan since 2025; SoftBank began reselling it there in September 2026.
When was Abnormal Security founded?
The company was founded in 2018 in San Francisco, capitalizing on the massive shift toward cloud-based email environments like Microsoft 365.
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