Alexander Rosen
Managing Partner & Co-Founder @ Ridge Ventures
San Francisco, United States
Alexander Rosen is a Series A investor at Ridge Ventures in San Francisco focused on Software and Analytics. Alexander Rosen is the Managing Partner & Co-Founder at Ridge Ventures.
- Total investments:
- 68
- Last investment:
- Lead investor:
- 24%
Last updated:
For AI agents: llms.txt
Industries Alexander Rosen invests in
Stages Alexander Rosen invests in
Countries Alexander Rosen invests in
Contacts
| Type | Contact | Validation |
|---|---|---|
| Work email | ||
| Personal email | ||
| Work phone | ||
| Personal phone | ||
| Socials |
Investment Focus
Industry
- Software 16 (24%)
- Analytics 10 (15%)
- Artificial Intelligence 10 (15%)
- Internet 8 (12%)
- Machine Learning 8 (12%)
Stage
- Series A 18 (26%)
- Seed 16 (24%)
- Series B 10 (15%)
- Series C 5 (7%)
- Venture - Series Unknown 4 (6%)
Country
- United States 42 (62%)
- Finland 1 (1%)
- United Arab Emirates 1 (1%)
Investments
| Company | Description | Round | Links |
|---|---|---|---|
| Horizon3.ai's mission is to help you find and fix your attack vectors before criminals exploit them. NodeZero, our automated penetration testing solution, enables organizations to continuously assess the security posture of their enterprise, including external, identity, on-prem, IoT, and cloud attack surfaces. Like APTs, ransomware, andother threat actors, our algorithms discover and fingerprint your attack surface, identifying the ways exploitable vulnerabilities, misconfigurations, harvested credentials, and dangerous product defaults can be chained together to facilitate a compromise. NodeZero is a true self-service SaaS offering that is safe to run in production and requires no persistent or credentialed agents. You will see your enterprise through the eyes of the attacker, identify your ineffective security controls, and ensure your limited resources are spent fixing problems that can actually be exploited. Founded in 2019 by industry, US Special Operations, and US National Security veterans, Horizon3.ai is headquartered in San Francisco, CA, and made in the USA. | $250M / Series E / Aug 03, 2026 | ||
| Triangle Tweener Fund seeks to create an index of private company investments in their early stages. Its goal is to create an index of Triangle-area early-stage, high-tech startups that meet the 'Tweener List' Criteria. | $15.3M / Seed / May 05, 2026 | ||
| GoodDay Software innovating on the most challenging problems facing commerce brands today. As former brand operators, we’re passionate about helping brands become more efficient and profitable, with fewer resources. | $7M / Venture - Series Unknown / Jan 15, 2026 | ||
| The holy grail of customer service is high quality affordable phone support. Previously? Impossible. Now? Easy. | $20M / Series A / Jan 13, 2026 | ||
| Bloom is the creator of an online data analysis platform that aims to transform data into revolutionary business outcomes. The firm platform uses artificial intelligence to give real time analytics and business insights, as well as interactive and enterprise data analytics, allowing business teams to monitor and make data-driven choices in realtime. | $1.5M / Seed / Aug 20, 2024 | ||
| OfferFit is an AI-powered experimentation platform that automates decision-making and personalization for businesses. It enables companies to optimize customer engagement strategies by continuously testing and learning from various offers and interactions. The platform leverages machine learning to deliver tailored recommendations, improvingmarketing effectiveness and customer experience. | $25M / Series B / Nov 14, 2023 | ||
| SafeGraph builds and maintains data sets to help accelerate machine learning and AI. Its high-precision places data covers business listings, building footprints, and aggregated foot traffic data for millions of points of interest (POI) and thousands of brands in the US and Canada. With detailed brand affiliation, spatial hierarchy, and other keybusiness details, SafeGraph data informs market analytics, investment research, site selection, and more.It was founded in 2016 and is based in San Francisco, California. | $45M / Series B / Mar 16, 2021 | ||
| Horizon3.ai's mission is to help you find and fix your attack vectors before criminals exploit them. NodeZero, our automated penetration testing solution, enables organizations to continuously assess the security posture of their enterprise, including external, identity, on-prem, IoT, and cloud attack surfaces. Like APTs, ransomware, andother threat actors, our algorithms discover and fingerprint your attack surface, identifying the ways exploitable vulnerabilities, misconfigurations, harvested credentials, and dangerous product defaults can be chained together to facilitate a compromise. NodeZero is a true self-service SaaS offering that is safe to run in production and requires no persistent or credentialed agents. You will see your enterprise through the eyes of the attacker, identify your ineffective security controls, and ensure your limited resources are spent fixing problems that can actually be exploited. Founded in 2019 by industry, US Special Operations, and US National Security veterans, Horizon3.ai is headquartered in San Francisco, CA, and made in the USA. | $3.5M / Seed / Jan 24, 2020 | ||
| Outlier offers analytic solutions that enable businesses to make better decisions. Moreover, Outlier monitors business data and notifies the user when unexpected changes occur. | $22.1M / Series B / Jan 22, 2020 | ||
| Tempered is a cyber risk management company that reduces cyber risks by providing point and click identity-based micro-segmentation. Its security and cloud network allow users to segment anything to achieve micro-segmentation for an IP resource without infrastructure change or disruption.Tempered Networks was founded in 2012 and is headquarteredin Seattle, Washington. | $17M / Venture - Series Unknown / May 08, 2019 | ||
| See all 68 investments → | |||
Co-Investors
About Ridge Ventures
Ridge Ventures funds experienced founders redefining how the world interacts with software. Whether for the cloud or the edge, we look for companies delivering advanced technologies, new distribution models and incredible user experiences to market. While we’re focused on SaaS and infrastructure solutions for the enterprise, we also back startups in adtech, gaming and ecommerce. We are firm believers in “where there’s a big problem, there’s a big opportunity.” We love Series A deals and helping create something out of chaos.
Ridge Ventures Contacts
| Name | Phone | Socials | |
|---|---|---|---|
Lorra Stone
CFO
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Yousuf Khan
Partner
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Akriti Dokania
Partner
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Alexander Rosen
Managing Partner & Co-Founder
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Derrick Lee
Chief Financial Officer
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FAQ
What does Alexander Rosen invest in?
Alexander Rosen invests primarily in Software, Analytics and Artificial Intelligence startups, most often at Series A and Seed stage. Most of the 68 investments tracked by Shizune back companies in United States. The Investment Focus section breaks down every industry, stage and country in the portfolio.
How do I contact Alexander Rosen?
Public channels for Alexander Rosen include LinkedIn and X (Twitter). For a verified work email and phone number, create a free Shizune account — contact data is searched across 20+ sources and validated before delivery, so your outreach lands in the right inbox.
When did Alexander Rosen last invest?
The most recent investment recorded for Alexander Rosen closed in Aug 2026. Shizune tracks 68 investments in total for this profile, including round sizes, stages and portfolio companies, all sourced from confirmed public funding rounds and refreshed monthly.
Is Shizune's investor data accurate?
Yes — every stat on this profile is calculated from confirmed public funding rounds monitored across hundreds of sources since 2020. This profile was last refreshed in Oct 2026 and is updated monthly. Spotted something off? Use the “Suggest an edit” link near the top of the page.
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