Keita Morikawa
Keita Morikawa, Co-Head of Agent Development (Japan) at Sierra | Venture Partner at Coreline Ventures | Exited founder, ex-CEO & Co-Founder of Opera | Angel investor | ex-McKinsey at Sierra, posted 3 times in the last 90 days. That is about 0.2 posts a week; the most recent went up on Oct 7, 2026. All of them were text-only posts. Everything in that window was an original post, no reshares. Sierra has 107 other people in the benchmark, including Reggie Marable, Bret Taylor and Shreya Sethi.
What format they post
Also posting at Sierra
Post counts are the public LinkedIn posts Imagine AI collects for this person, taken over the 90 days to Oct 7, 2026; reshares are left out of the post count and the format mix. Follower counts come from the last profile check. The band compares a typical post, the geometric mean of reactions on posts that have had two weeks to settle, with the Imagine AI research baseline of 20,000+ posts from B2B startups. How the benchmark is built.
