You asked about B2B
Nobody in the register described anything this way.
| Launched | What it was | Today |
|---|---|---|
| 2021-01-01 | YCR2 Embedded lending infrastructure · r2.co | acquired |
| 2021-06-01 | YCMailmodo No-code email marketing platform to send forms & widgets within emails · mailmodo.com | acquired |
| 2021-01-01 | YCDyte Real-time audio & video SDKs, ready to launch 🚀 · dyte.io | acquired |
| 2021-06-01 | YCDeed Making it easy for employees to donate and volunteer with good causes. · joindeed.com | acquired |
| 2021-06-01 | YCGoodkind Student communications platform for higher education · goodkind.com | acquired |
| 2021-01-01 | YCUiflow No-code platform for enterprise software companies · ycombinator.com | acquired |
| 2021-06-01 | No-code scoring engine identifying your most engaged upsell opps · breadcrumbs.io | acquired |
| 2021-06-01 | YCAer Compound compliance: the central hub for meeting SEC obligations · aercompliance.com | acquired |
| 2021-01-01 | YCPreki Shopify for LatAm · preki.com | acquired |
| 2021-01-01 | Digital Sales Rooms (Acquired by MindTickle) · enableus.com | acquired |
| 2021-01-01 | Dramatically better search and ads for marketplaces · promoted.ai | acquired |
| 2021-01-01 | YCJourney No code platform for sales to tell better stories and win more deals. · journey.io | acquired |
| 2021-01-01 | YCTrendpop Discover trends as they happen · trendpop.com | acquired |
| 2021-06-01 | YCTarsal Data pipeline for your security data lake. · tarsal.co | acquired |
| 2021-06-01 | Direct Ordering Software for Restaurants · tablevibe.co | acquired |
| 2021-06-01 | YCArengu Build frictionless signup flows in minutes · arengu.com | acquired |
| 2021-06-01 | AI-Powered Business Development for Scientific Organizations · firstignite.com | acquired |
| 2021-01-01 | Supercharge your mobile apps · emergetools.com | acquired |
| 2021-01-01 | Build better computer vision models by building better datasets · segments.ai | acquired |
| 2021-06-01 | Eliminate Cloud Waste. Attribute and Track Savings. Engage Engineers. · cloudthread.io | acquired |
| 2021-01-01 | YCunSurvey AI-led market research interviews, no scheduling, instant insights. · unsurvey.ai | acquired |
| 2021-01-01 | YCAvenue Observability platform for operations teams · avenue.app | acquired |
| 2021-01-01 | YCPingPong Video messaging app for remote teams. · getpingpong.com | acquired |
| 2021-01-01 | Helping food brands and retailers reduce food wastage · fountain9.com | acquired |
| 2021-01-01 | Finance for Founders (now at prune.com) · pry.co | acquired |
| 2021-01-01 | Manage your hybrid workplace · worksphere.com | acquired |
| 2021-06-01 | YCTelivy Automate your cyber security risk assessments · telivy.com | acquired |
| 2021-06-01 | Increasing restaurant profitability through our AI Operating System · bytekitchen.io | acquired |
| 2021-01-01 | YCeqtble Turning HR data into actionable insights · eqtble.com | acquired |
| 2021-01-01 | Business intelligence on text · hyperglue.com | acquired |
| 2021-01-01 | YCFlok End to end company retreat planning · goflok.com | acquired |
| 2021-01-01 | A faster and more collaborative alternative to Jira for remote teams · kitemaker.co | acquired |
| 2021-06-01 | YCMaroo CRM for creatives (acquired by Helium Ventures) · maroo.us | acquired |
| 2021-06-01 | YCSleek Browser automation for businesses. · onsleek.com | acquired |
| 2021-01-01 | Open source continuous profiling software to debug performance issues · pyroscope.io | acquired |
| 2021-06-01 | A modern platform for content marketing & SEO. · positional.com | acquired |
| 2021-06-01 | YCHilos Close and activate your customers on WhatsApp · hilos.io | acquired |
| 2021-06-01 | YCKeyri Secure fraud prevention and authentication platform for developers · keyri.com | acquired |
| 2021-06-01 | YCLaudable App for B2B companies to find customer stories and advocates · laudable.com | acquired |
| 2021-06-01 | YCSatsuma Reliable blockchain indexing & querying for web3 engineering teams. · satsuma.xyz | acquired |
| 2021-01-01 | YCStacksi Automated Answers to Security Questionnaires · stacksi.com | acquired |
| 2021-06-01 | YCOnfolk Gusto for the UK · onfolk.com | acquired |
| 2021-01-01 | YCProcoto Self-service RFP management · procoto.com | acquired |
| 2021-01-01 | YCTechBiz MIS on mobile for SMB's in India · techbiz.app | acquired |
| 2021-06-01 | YCWarrant Authorization and access control as a service. · warrant.dev | acquired |
| 2021-06-01 | YCBytebot Bytebot is the open source container for AI desktop agents. · bytebot.ai | acquired |
| 2021-01-01 | Open source mobile marketing platform. Alternative to appcues /… · laudspeaker.com | acquired |
| 2021-06-01 | YCPactima Live video signing for real-time agreements · pactima.com | acquired |
| 2021-06-01 | YCVogent Build Voice AI Agents · vogent.ai | acquired |
| 2021-06-01 | YCMentum AI-Powered Assistant for Procurement and Strategic Sourcing · getmentum.com | acquired |
| 2021-01-01 | The network where sales teams connect to share customer introductions. · partnered.com | acquired |
How this compares
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.