You asked about Cybersecurity
35 people built something like it. 0 are gone.
That is 0% of the ones whose fate we could settle, against 23% across the whole register.
| Launched | What it was | Today |
|---|---|---|
| 2019-06-01 | YCTRM Labs TRM is building a safer world for billions of people. · trmlabs.com | still up |
| 2016-01-01 | Protects organizations from getting breached through their APIs. · salt.security | still up |
| 2020-01-01 | YCRiot Cybersecurity awareness for fast growing companies · tryriot.com | still up |
| 2024-01-01 | Autonomous offensive and defensive cybersecurity platform · codeant.ai | still up |
| 2019-01-01 | YCMedCrypt MedCrypt gives medical device vendors cybersecurity features in a few… · medcrypt.co | still up |
| 2022-06-01 | Enterprise software for enterprise risk and cyber fraud intelligence · overwatchdata.ai | still up |
| 2023-01-01 | The Control Plane for Enterprise Agents · credal.ai | still up |
| 2020-01-01 | YCSkypher AI agent for Compliance Questionnaires Automation · skypher.co | still up |
| 2023-01-01 | YCVariance AI Agents for Fraud Review and Investigations · variance.com | still up |
| 2020-06-01 | YCFormal Take control of your data in real-time. · joinformal.com | still up |
| 2024-06-01 | YCZeroPath Automatically find and fix your software vulnerabilities · zeropath.com | still up |
| 2021-06-01 | AI-driven mobile cybersecurity · mallocprivacy.com | still up |
| 2025-09-01 | YCComplyDo Global Compliance for Enterprises · complydo.io | still up |
| 2024-06-01 | YCUnbound Use AI tools without fear of data leakage · getunbound.ai | still up |
| 2023-06-01 | YCCorgea Corgea finds, and fixes insecure code and packages autonomously. · corgea.com | still up |
| 2025-06-01 | YCGhostEye Your always-on red team. · ghosteye.ai | still up |
| 2023-08-14 | beyondmachines.net | still up |
| 2026-06-01 | YCCaution Hosting platform for software you can't afford to have hacked · caution.co | still up |
| 2025-09-01 | YCAntigen Continuous offensive security for the enterprise. · antigen.sh | still up |
| 2023-06-01 | Firmware cybersecurity · metalware.com | still up |
| 2026-06-01 | Autonomous AI defense system for cyber attack · nebusec.ai | still up |
| 2026-06-01 | YCTrident Autonomous offensive security agents. The best defense is offense · tridentsecurity.io | still up |
| 2026-06-01 | AI cybersecurity for financial institutions' digital assets · verdictmachine.com | still up |
| 2025-01-01 | YCCandor Protect your data and stop insider risk · candor.security | still up |
| 2025-01-01 | YCArchon We help software companies sell to government. · archon.inc | still up |
| 2025-09-01 | Continuous AI pentesting that finds and fixes vulnerabilities · verialabs.com | still up |
| 2026-06-01 | YCFabraix The world's frontier hacker of AI agents. · fabraix.com | still up |
| 2025-06-01 | Visibility and Controls for Browser Agents · contextfort.ai | still up |
| 2026-06-01 | CrowdStrike for AI Agents · traceforce.ai | still up |
| 2023-01-01 | YCMatano Cloud Native SIEM (alternative to Splunk/Elastic) · matano.dev | still up |
| 2024-09-01 | The AI Security Engineer to Find and Fix Vulnerabilities · gecko.security | still up |
| 2026-01-01 | The control plane for AI agents. · agenticfabriq.com | still up |
| 2025-09-01 | The sensitive data redaction layer for AI · logosguard.com | still up |
| 2026-06-01 | YCPalisade AI that finds and fixes OS-level vulnerabilities across device fleets · palisade-ai.com | still up |
| 2024-01-01 | LLM Security and Compliance · promptarmor.com | still up |
How this compares
Y Combinator reports its own outcomes, including acquisitions. The other two are judged by asking the domain, so they are not measured the same way and are never averaged together.
The register re-probes every domain it holds. Some that answered last month stop answering. We send that list — what went quiet, and what it was — once a month. Nothing else.
How this was made. Show HN entries are every post from 2021 to 2023 with at least five points that linked to its own domain; code hosts and free hosting are excluded, because a repository outlives the effort behind it. Product Hunt entries needed 100 votes — a far higher bar, so they are the promoted top slice rather than a like-for-like sample. Both are judged by asking the domain whether it still answers: gone means it no longer resolves, refuses the connection, serves a parking page, or says plainly that it shut down. An HTTP error is not counted as gone — a server answering 404 is one somebody still pays for, and an audit of 25 gone-calls found two such sites alive with only a moved homepage. Y Combinator entries use the status YC publishes itself, which is why only those can say acquired. Squatted domains — a lapsed name now serving somebody else's site — are not detected, so these figures run slightly low.