Growth Hub #16 - By Founders, For Founders w/ Keita Morikawa (Opera Tech → Sierra)
The Growth Hub is our regular gathering for an open exchange on the realities of building and scaling ventures in Japan.
Back in March, one of Silicon Valley's hottest AI companies acquired a 17 months old Tokyo startup.
The buyer was Sierra - a customer-experience AI agent company founded by Bret Taylor (chairman of OpenAI, former co-CEO of Salesforce) and Clay Bavor (ex-Google). Sierra has raised over $630M, is now valued at around $15 billion, and is building the "Agent OS" that automates customer support and sales for global brands. The startup they acquired was Opera Tech, founded in late 2024 by Keita Morikawa (CEO) and Kiyohito Kunii (CTO).
Opera sits inside a run of acquisitions alongside Receptive AI and the French YC startup Fragment. The unicorn was looking for teams that understood how to deploy autonomous AI agents inside its respective market enterprises.
Homegrown software startups seldom exit to tier-1 Silicon Valley giants this early. Keita went from consultant in London, to founder in Tokyo, to a cross-border exit, to now leading AI agent development at Sierra Japan. It's a blueprint few founders here have ever drawn.
At Growth Hub #16, Keita joins us to walk through the whole arc:
The original thesis - why he left McKinsey to build this, and how he spotted the problem
Winning the first Japanese enterprise customers
The cross-border path and building the founding team
How the Sierra relationship formed - and how the acquisition came together
What it actually to build inside one of the world's fastest-moving AI companies
Steering the conversation is our guest moderator, Kenneth Jeng, joining the Growth Hub team for this session.
Special thanks to Stéphane E. Fouché and Mari Matsuzaki, who helped make this session happen.
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