Michael Seibel

Michael Seibel
Name	Michael Seibel
Birth date	1982
Birth place	Detroit, Michigan, United States
Occupation	Entrepreneur, investor, executive
Known for	CEO of Justin.tv, CEO of Twitch, Partner at Y Combinator

Michael Seibel is an American entrepreneur and investor notable for his leadership in streaming technology and startup acceleration. He co‑founded and led influential platforms that reshaped live video and supported early‑stage companies, and later joined a prominent startup accelerator where he guided many founders across Silicon Valley and global hubs. His career intersects with multiple notable companies, institutions, founders, and events in the technology and venture capital ecosystems.

Early life and education

Seibel was born in Detroit, Michigan and raised in a family that influenced his interest in technology and entrepreneurship. He attended Yale University, where he studied and engaged with campus groups and local New Haven initiatives that connected students to startup culture. During his university years he encountered peers and future collaborators who later played roles at organizations such as Justin Kan, Emmett Shear, and other early streaming pioneers. His formative years overlapped with broader shifts in Silicon Valley trends, including the rise of platforms like YouTube, Facebook, and Myspace.

Career

Seibel co‑founded and served as CEO of Justin.tv, an early live‑streaming platform developed by a team including Justin Kan and Emmett Shear, which later spun off a gaming‑focused service that became Twitch. After leadership at Justin.tv and Twitch, he co‑founded and led other ventures and became an active participant in startup ecosystems that included investors and executives from Sequoia Capital, Andreessen Horowitz, Accel Partners, and Benchmark. His career trajectory connected him to founders from companies like Dropbox, Airbnb, Stripe, Reddit, and GitHub.

Y Combinator and venture capital

Seibel joined Y Combinator as a part‑time partner and later became a partner and CEO of the accelerator’s startup programs, working alongside partners such as Paul Graham, Jessica Livingston, Sam Altman, Trevor Blackwell, and Garry Tan. In that role he advised hundreds of startups participating in batches that featured companies like Coinbase, DoorDash, Instacart, Rappi, and Brex. He oversaw admissions, mentorship, and demo day preparations during periods when Y Combinator expanded initiatives into regions including Asia, Africa, and Europe. His investment and mentoring work connected him with angel investors and venture firms including Founders Fund, Google Ventures, Kleiner Perkins, and Lightspeed Venture Partners.

Public speaking and media appearances

Seibel has appeared on panels, podcasts, and conferences alongside figures such as Marc Andreessen, Ben Horowitz, Reid Hoffman, Elon Musk, and Mark Zuckerberg. He has spoken at venues including TechCrunch Disrupt, SXSW, TEDx, Web Summit, and academic institutions like Stanford University and Massachusetts Institute of Technology. Media outlets and programs that have featured him include The New York Times, The Wall Street Journal, CNBC, Bloomberg L.P., and podcasts such as The Tim Ferriss Show and How I Built This.

Board memberships and investments

Seibel has served on boards and advised startups that later gained backing from firms like Tiger Global Management, SoftBank Group, and Benchmark. His investments and mentorship include early involvement with companies in fintech, healthtech, and developer tools sectors such as Coinbase, Twitch, Docker, Ginkgo Bioworks, and Notion. He has worked with founders who later connected with corporate partners including Amazon Web Services, Microsoft, Facebook, and Google Cloud Platform.

Personal life and advocacy

Seibel is known for advocacy on founder diversity, inclusion, and access to venture funding, aligning with initiatives involving organizations such as Black VC, All Raise, StartOut, and university entrepreneurship programs at Yale University and Stanford University. He has participated in public discussions addressing representation involving figures and groups like Barack Obama, Kamala Harris, and civil society organizations. Outside of work he has been associated with community organizations and philanthropic efforts that collaborate with institutions including Khan Academy, DonorsChoose, and regional nonprofit networks.

Category:American chief executives Category:Y Combinator people