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  1. Home
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  3. Michael Seibel
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Michael Seibel

Michael Seibel

Managing Director at Y Combinator, Co-founder of Twitch and Justin.tv

BornOctober 27, 1982 (age 41)
NationalityAmerican
FirmY Combinator
EducationYale University (B.A. Political Science)
Known ForTwitch, Justin.tv, Y Combinator
SocialTwitter, LinkedIn
LinkedInLinkedInXXWebsite
Investor
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About Michael Seibel

Michael Seibel is a prominent figure in the startup and venture capital world, best known for his roles as a co-founder of Twitch (acquired by Amazon for $970 million) and Justin.tv. He currently serves as the Managing Director of Y Combinator, one of the most prestigious startup accelerators globally.

Seibel's journey in tech began early, leading him to build and sell successful companies before transitioning into his influential role at Y Combinator. His experience as a founder gives him a unique perspective on the challenges and opportunities faced by early-stage startups, making him a highly respected mentor and investor.

Net Worth

Michael Seibel's net worth is primarily derived from the successful acquisition of Twitch by Amazon for $970 million, his previous ventures, and his ongoing involvement with Y Combinator. While specific figures for his personal net worth are not publicly disclosed, his significant equity stakes in these ventures and his role at Y Combinator suggest a considerable valuation.

Investments & Exits
Twitch
Co-founder, acquired by Amazon for $970 million.
Justin.tv
Co-founder, platform that evolved into Twitch.

Investment Strategy

Michael Seibel's investment strategy is deeply influenced by his experience as a founder and his role at Y Combinator. He primarily focuses on early-stage companies, often pre-seed or seed rounds, looking for strong founding teams and innovative solutions to significant problems. His portfolio reflects a broad interest across various sectors, including- SaaS, developer tools, fintech, and consumer internet.

At Y Combinator, Seibel emphasizes the importance of "default alive" – ensuring companies can sustain themselves with their current burn rate and runway. He is also a proponent of rapid iteration, strong product-market fit, and efficient capital utilization. His advice often centers on building a robust foundation, understanding customer needs, and executing effectively rather than solely focusing on fundraising.

Notable Quotes

“Build something people want.”

— Michael Seibel

“The fastest way to learn is by doing.”

— Michael Seibel

“Don't optimize for fundraising. Optimize for building a great product.”

— Michael Seibel

Contact Information

Connecting with Michael Seibel can be best achieved through official channels associated with Y Combinator. For startup founders seeking investment or mentorship, applying to the Y Combinator program is the most direct route to engage with him and his team.

For general inquiries, media requests, or speaking engagements, it is advisable to contact Y Combinator's public relations or administrative departments. Michael is also active on Twitter, where he shares insights and occasionally interacts with the community.

Use Lessie to find verified contact information, mutual connections, and the best outreach strategy for reaching Michael Seibel and similar investors.

Contact via Lessie

Publications

Michael Seibel regularly shares his insights on startups, fundraising, and entrepreneurship through the Y Combinator blog and various interviews. While he may not have a personal list of standalone publications, his contributions to the YC blog serve as a rich resource for founders.

He has also been featured in numerous articles and interviews in prominent tech and business publications, discussing topics ranging from the early days of Twitch to the evolving landscape of startup acceleration at Y Combinator.

Podcast

Michael Seibel is a frequent guest on various podcasts and has conducted numerous interviews where he shares his expertise on startups, investing, and scaling businesses. He often appears on podcasts related to Y Combinator's initiatives, offering advice to aspiring founders.

Notable appearances include discussions on the Y Combinator podcast, where he delves into specific aspects of the startup journey, and interviews on other popular tech and entrepreneurship podcasts, providing valuable insights from his experience at Twitch, Justin.tv, and Y Combinator.

Related Profiles

Paul Graham

Co-founder of Y Combinator

Jessica Livingston

Co-founder of Y Combinator

Sam Altman

Former President of Y Combinator

Garry Tan

President and CEO of Y Combinator

Alexis Ohanian

Co-founder of Reddit and Early Stage Investor

Kevin Hale

Partner at Y Combinator

Dalton Caldwell

Partner at Y Combinator

Harj Taggar

Co-founder and CEO of Triplebyte (YC alum)

Bill Gates

Co-founder of Microsoft, Co-chair of the Bill & Melinda Gates Foundation, Investor

Frequently Asked Questions

Who is Michael Seibel?

Michael Seibel is an American entrepreneur, investor, and the Managing Director of Y Combinator. He is also a co-founder of Twitch and Justin.tv.

What is Michael Seibel known for?

Michael Seibel is widely recognized for co-founding Twitch (acquired by Amazon for $970 million) and Justin.tv, as well as for his leadership role as the Managing Director of Y Combinator.

What companies has Michael Seibel invested in?

As the Managing Director of Y Combinator, Michael Seibel has been instrumental in the funding and mentorship of thousands of startups, including significant early investments in companies like Airbnb, Stripe, Dropbox, and Coinbase. His personal investments often align with YC's portfolio.

What is Michael Seibel's investment philosophy?

Seibel's investment philosophy focuses on identifying strong founding teams, scalable business models, and companies addressing large markets. He emphasizes the importance of product-market fit, efficient execution, and sustainable growth, often advocating for a 'default alive' mindset among startups.

How can I contact Michael Seibel?

Due to his prominent role at Y Combinator and his extensive commitments, direct contact with Michael Seibel is generally made through official Y Combinator channels or professional networking. He is active on Twitter, which can also be a way to engage with his insights.

What is Michael Seibel's net worth or fund size?

While Michael Seibel's personal net worth is not publicly disclosed, it is substantial due to his co-founding roles at Twitch (acquired for $970 million) and Justin.tv, as well as his equity and compensation from Y Combinator. Y Combinator itself has invested in thousands of companies, representing a collective valuation in the hundreds of billions.

What are some notable quotes by Michael Seibel?

One notable quote often attributed to Michael Seibel regarding startups is: 'Build something people want.' He also frequently advises founders to 'talk to your users' and 'launch fast.'

What are Michael Seibel's career highlights?

Key career highlights include co-founding Justin.tv in 2007, co-founding Twitch in 2011 (which was acquired by Amazon in 2014 for $970 million), and becoming a Partner at Y Combinator in 2013, eventually rising to Managing Director. He also served as CEO of Posthaven prior to YC.

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