Yotam Segev

Background

Yotam Segev is the co-founder and CEO of Cyera, a data security company valued at $9 billion as of January 2026 ¹. He earned a Bachelor of Science in Computer Science and Physics from The Hebrew University of Jerusalem (2010-2013) ². He attended the Mandel Leadership Institute for Educational Leadership in the Military (2017-2018) and was a Nativ Program Fellow at IDEA - Israeli Center for Liberal Democracy, studying Political Science and Government (2019-2020) ².

Segev’s career began in the Israeli Defense Forces, where he served in the elite Talpiot Leadership Academy as a Senior Class Commander ³. He then served in Israeli Military Intelligence Unit 8200, where he held roles including Cyber Team Lead (2015-2016), Cyber Course Instructor (2015), and Head of the Cyber Department (2018-2020) ². Together with his future co-founder Tamar Bar-Ilan, he founded, built, and ran Unit 8200’s cloud security division ³.

In 2021, Segev and Bar-Ilan co-founded Cyera ³. Before building the product, they interviewed over 100 CISOs to understand pain points in data security ⁴. Cyera emerged from stealth in March 2022 with $60 million in funding led by Sequoia Capital, alongside Accel and Cyberstarts ³. The company has since raised over $1.7 billion in total funding across six rounds, reaching a $9 billion valuation in its January 2026 Series F led by Blackstone Growth ¹. Investors include Sequoia Capital, Accel, Cyberstarts, Coatue, Redpoint, Lightspeed Venture Partners, Greenoaks, Georgian, Sapphire Ventures, and Spark ¹. Segev was named a Sequoia Capital founder in 2022 ⁵. Cyera employs approximately 1,100 people as of January 2026 ⁶.

Segev is primarily known as an operator and founder rather than a professional investor. His angel investing activity is limited and focused exclusively on Israeli cybersecurity startups founded by fellow Unit 8200 and Talpiot alumni.

Stated Thesis

Segev has not published a formal investment thesis. His angel investments appear to be driven by personal relationships within the Israeli cybersecurity community rather than a systematic investment strategy. Based on his public statements, his worldview centers on data security as the foundational layer of enterprise AI adoption.

On the importance of data security, Segev has stated: “Data needs to be everywhere. Data is being used by every business unit, and data is driving tremendous business value” ⁷. He has described AI security as “where the biggest gap is today for enterprises,” noting that companies “just have no control over their data, and AI runs on data” ⁸.

His angel investments in companies like Daylight Security (AI-native managed security) and Spirit (enterprise information security) suggest a preference for cybersecurity companies that apply AI to security operations, founded by teams with Israeli military intelligence backgrounds.

Inferred Thesis

Based on 3 verified angel investments, the sample size is too small for reliable percentage breakdowns. Qualitative observations only:

Sector focus: All 3 verified investments are in cybersecurity/security operations. No investments found outside the security domain.

Stage distribution: All verified investments are at seed stage, though Segev also participated in Daylight Security’s Series A follow-on ⁹.

Geographic focus: All 3 portfolio companies are Israeli-founded cybersecurity startups.

Founder profile pattern: All known portfolio company founders are graduates of the IDF’s Talpiot program and/or Unit 8200 alumni — the same military programs where Segev served. This is a strong signal of network-driven investing.

Co-investor patterns: Segev frequently co-invests alongside other Israeli cybersecurity founder-CEOs, particularly Assaf Rappaport (Wiz) and the Torq co-founders (Ofer Smadari, Leonid Belkind, Eldad Livni). His Cyera co-founder Tamar Bar-Ilan also participates in the same rounds ⁹¹⁰.

Investment pace: With only 3 verified investments over approximately 2 years (2025-2026), Segev appears to be a very selective, occasional angel investor rather than an active or prolific one. His primary focus remains building and scaling Cyera.

Notable context: Segev’s angel investing is best understood as a byproduct of his position as a leading Israeli cybersecurity CEO. He invests in founders he knows personally from military service, not as a deliberate portfolio-building exercise.

Portfolio

This table represents Segev’s entire verified angel portfolio. Tracxn lists 2 portfolio companies ¹². Only investments with confirmed sources are included. Segev’s primary professional activity is as CEO of Cyera, not as an investor.

In Their Own Words

“The hands-on experience leading Unit 8200’s cloud security initiative gave us a real sense of both the promise and the challenges in this space. We saw just how fast data moved, replicated, and multiplied in the cloud, and how traditional approaches simply couldn’t keep pace.” — Yotam Segev, Cyera stealth launch press release, March 2022 ³.

“We wanted to build something that will outlast us. Something that would be a big company, a memorable company, a company that will really make an impact in the industry.” — Yotam Segev, Cyera podcast, Cyber Inspiration Episode 47 ⁷.

“Our business had legs before AI. But with AI, it’s got wings.” — Yotam Segev, Fortune, January 2026 ⁶.

“We’re chasing agentic attackers, and these attackers are going to be much more honed, much more put together, and much more consistent and reliable in their actions and delivery at millisecond speed.” — Yotam Segev, Fortune, January 2026 ⁶.

“If they don’t have the data security done right, they just have no ability to say ‘Yes’ to AI in the way they want to.” — Yotam Segev, Fortune, January 2026 ⁶.

“We allow these enterprises to move quickly with AI but to do it responsibly and securely.” — Yotam Segev, Calcalist/CTech interview, March 2025 ⁸.

“AI for us is core to what we do on both sides of the fence.” — Yotam Segev, Calcalist/CTech interview, March 2025 ⁸.

“We’re talking about the most transformative technology our generation has seen.” — Yotam Segev, Calcalist/CTech interview, March 2025 ⁸.

What Founders Say

No independently sourced founder testimonials found about Yotam Segev as an angel investor. As a CEO/founder rather than a professional investor, founder feedback about his investing activity is not publicly available. Lior Simon, partner at Cyberstarts (seed investor in Cyera), has praised Segev’s execution: “What Yotam, Tamar and the team have managed to build in under a year is incredible” ³, though this is an investor comment about Segev as a founder, not a founder comment about Segev as an investor.

Sources