Y Combinator

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Y Combinator YC turns builders into formidable founders [1] Airbnb Brian, Joe, and Nate did YC in W09. Airbnb went public in 2020 at an over $100B valuation. YC Now OpenAI Sam was part of YC s inaugural batch in S05 and founded OpenAI as YC Research in 2015. Sam built OpenAI into a $500B company. YC Now Stripe The Collison brothers did YC twice—first in W07 and then in S09, when they started Stripe. Stripe is now the internet’s $107B payments backbone. YC Now Coinbase Fred and Brian met on Reddit and did YC in S12. Coinbase went public in 2021 at a $86B valuation. YC Now DoorDash Andy, Stanley, Tony, and Evan did YC in S13. DoorDash went public in 2020 at a valuation of $39B. YC Now Scale AI Alexandr and Lucy did YC S16 and pivoted during the batch. In 2025, Meta acquired 49% of Scale for over $14B. YC Now Dropbox Arash and Drew started Dropbox at MIT and did YC in S07. Dropbox had the biggest tech IPO of 2018 at a $9B valuation. YC Now Reddit Alexis and Steve were in the inaugural YC batch in S05. Reddit went public in 2024 at a $6.4B valuation. YC Now Instacart Apoorva, Max, and Brandon did YC in S12. Instacart went public in 2023 at a $10B valuation. YC Now GitLab Sid and Dmytro did YC in S14. GitLab went public in 2021 at an $11B valuation. YC Now Kalshi Tarek and Luana did YC in W19. Kalshi reached an $11B valuation in 2025. YC Now Replit Haya and Amjad interviewing for the YC W18 batch. Replit became a leading AI coding platform valued at over $9B. YC Now Twitch Michael

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