Doi Ken's New Book: Transforming Offline Advertising in a GAFA-Free World

In an age dominated by digital advertising driven by GAFA (Google, Apple, Facebook, Amazon), Doi Ken, the representative director of ohpner Inc., is set to release a groundbreaking book titled "Offline Advertising Revolution: Transforming Advertising in a GAFA-Free World". Scheduled for launch on October 31, 2025, by the publishing firm, Senden Kaigi, this book takes a bold stance against the current digital marketing trends. Reservations for this compelling read have already opened on Amazon, making it accessible for those eager to dive into innovative marketing strategies.

The book explores the dramatic evolution of offline marketing through various mediums including mobility advertising, taxi advertising, television commercials, and radio ads. Doi shares his insights on what led to his continual success in a landscape that has traditionally favored online advertising techniques.

Contents Overview

Table of Contents:
1. The Rise of Mobility Advertising: Why National Clients are Taking Notice
2. The 'Offline Advertising Revolution': Winning in a GAFA-Free World
3. Inventing Mobility Advertising: Creating Value Acknowledged by National Clients
4. The Current and Future Landscape of Taxi Advertising
5. Taking on Radio: New Business Models Emerged
6. Successful Strategies for Vertical Startups: How to Create New Ventures

Through these chapters, Doi reveals not just his journey but the myriad planning and strategy behind the launch and growth of various offline advertising ventures. Having transitioned from digital to offline marketing, Doi reflects upon his unique perspective and innovative strategies that have led to his success.

Collaborative Insights

The book also features interviews with top executives like Hiroshi Nakajima from GO, Yoshihiro Okada from Progrit, Ryo Yoshioka from Willgate, and Ryo Suma from GRAND. These discussions shed light on industry trends, highlight the shifting paradigms in advertising, and provide readers with expert insights on the future of marketing beyond digital confines.

Author's Background

Doi Ken's achievements stem from a solid academic background. After graduating from Doshisha University, he joined CyberAgent, where he laid the groundwork for their mobile advertising agency. Later, in 2011, he transitioned to EC Navi (now part of CARTA HOLDINGS), contributing significantly by helping in the establishment of SSP fluct. Within a span of a few years, he was instrumental in raising its revenue from ¥2 billion to ¥11.4 billion, solidifying it as one of Japan's largest SSPs and paving the way for its parent company's transition to a publicly listed entity.

Following key roles as an executive officer at VOYAGE GROUP and then as the CEO of fluct, Doi took the reins in 2021 as the CEO of Teracy, achieving remarkable growth with revenues reaching ¥7.8 billion by the third year before stepping down in March 2024. After gaining independence in the same year, Doi now leads ohpner, focusing on media development, including mobility advertising—the former Ad Truck. In an exciting turn, he invested in Radio Osaka in August 2025, stepping into the radio industry as a major shareholder and external director.

About ohpner

ohpner Inc. is committed to supporting business growth through offline advertising and marketing consulting. They provide comprehensive marketing solutions, encompassing media selection, creative production, ad delivery, and effect measurement through mobility advertising, taxi advertising, transportation advertising, and other out-of-home (OOH) options.

Book Details:

- Title: Offline Advertising Revolution: Transforming Advertising in a GAFA-Free World
- Author: Doi Ken (Representative Director of ohpner Inc.)
- Release Date: October 31, 2025
- Price: ¥2,310 (including tax)
- Publisher: Senden Kaigi