Company name
Coursebase, Inc.

Incorporation date
March 26, 2012

Capital stock
400 million yen

Shibuya-ku, Tokyo 150-0001
3-42-2 Jingumae
VORT Gaienmae III, 7F

John Martyn (Hideyoshi Kuroda)
Billy Martyn (Kosuke Kuroda)

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John Martyn

John Martyn (Hideyoshi Kuroda)

Co-Founder / Co-CEO

John co-founded Coursebase with his brother Billy and childhood friend Franky in 2012. As Co-Founder and Co-CEO, John leads Coursebase’s sales, partnerships and investor relations. Before co-founding Coursebase, John worked at asset management firm BlackRock in New York where he managed sales and relationships with Japanese institutional clients. John graduated from George Mason University in 2007 with a B.A. in Global Affairs and studied abroad at Sophia University in 2006. John is bilingual in English and Japanese.

Billy Martyn

Billy Martyn (Kosuke Kuroda)

Co-Founder / Co-CEO

Billy co-founded Coursebase with his brother John and childhood friend Franky in 2012. As Co-Founder and Co-CEO, Billy leads Coursebase’s product design, product management and business operations. Before co-founding Coursebase, Billy worked at investment bank Credit Suisse and at financial data firm Bloomberg in Tokyo where he led the Futures & Options desk in Asia. Billy graduated from the University of Virginia in 2008 with a B.A. in Foreign Affairs and Japanese Language and Literature, and studied abroad at Kyoto University in 2007. Billy is bilingual in English and Japanese.

Frank Chung

Frank Chung

Co-Founder / CTO

Franky co-founded Coursebase with his childhood friends Billy and John in 2012. As Co-Founder and CTO, Frank leads Coursebase’s engineering. Before co-founding Coursebase, Frank worked at Deloitte Consulting in Washington D.C. where he led several systems integration projects for government clients. Franky graduated from the University of Virginia in 2009 with a B.S. in Information Technology and Finance.


Digital Garage


Digital Garage is Japan’s leading startup incubation and investment firm. Founded in 1995 by internet pioneers Kaoru Hayashi and Joi Ito, Digital Garage has been early investors in many successful startups including Twitter and Path. The firm is headquartered in Tokyo and has an office in San Francisco.



PERSOL HOLDINGS is one of Japan’s leading HR services companies and provides a wide range of services in Japan and across Asia including recruiting, temporary staffing and consulting. Through its corporate venture capital fund PERSOL VENTURE PARTNERS, PERSOL HOLDINGS invests in innovative companies with technologies and/or services in the HR domain.

CyberAgent Capital


CyberAgent Capital is a leading early stage venture capital firm based in Tokyo with offices in China, Taiwan, Korea, Vietnam, and Indonesia. Founded in 2006, CyberAgent Capital was an early investor in Japanese social network Mixi and Chinese video-sharing service Tudou.com.

Sunbridge Global Ventures


Sunbridge Global Ventures is a seed fund and startup accelerator focused on investing in Japanese startups with global potential. Headquartered in Tokyo, the firm also has offices in Osaka and Silicon Valley.

500 Startups

Silicon Valley

500 Startups is a Silicon Valley seed fund and startup accelerator. With a global network of hundreds of experienced startup mentors, a creative working space in the heart of Silicon Valley, and a vibrant community of startup founders, the 500 Startups network is taking the world by storm.


PERSOL HOLDINGS and Digital Garage invest in Coursebase

HR services company PERSOL HOLDINGS CO., LTD. (Headquartered in Tokyo, Japan, President and CEO: Masamichi Mizuta) and internet technology company Digital Garage, Inc. (Headquartered in Tokyo, Japan, President and CEO: Kaoru Hayashi) made an equity investment in Learning Management System (LMS) provider Coursebase, Inc. (Headquartered in Tokyo, Japan, Co-CEO: John Hideyoshi Martyn, Billy Kosuke Martyn). The investment was made through the corporate venture capital funds PERSOL INNOVATION FUND LLC and DG Incubation, Inc.

Press release of PERSOL HOLDINGS:


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