KB Ken G. Brook III

Ken G. Brook III • Founder • Entrepreneur • Operator

Building companies where adtech, AI, and market infrastructure converge.

Ken is a seasoned entrepreneur with more than a decade of experience building technology companies across advertising, blockchain-based trust systems, and AI-powered marketing infrastructure. He has founded six ventures, repeatedly turning technical shifts into practical, revenue-producing products.

LinkedIn Crunchbase
6 companies founded Boise, Idaho Adtech, AI, blockchain

Professional Bio

Ken Brook builds companies around inflection points.

Ken’s career has been defined by a repeatable founder pattern: enter markets that are fragmented, opaque, or operationally inefficient, then build the infrastructure layer that makes them easier to use, easier to trust, and easier to scale. That pattern has carried across cross-screen media, video monetization, blockchain-based ad transparency, and AI-native marketing automation.

He has founded and led ventures including StreamRoll Media, VidRoll, MetaX and adChain, and AdPrompt. Across those chapters, he has consistently worked at the intersection of product vision, commercial execution, and technical leverage.

How He Operates

What consistently defines his approach.

Category Sense

Identifies markets where complexity has outrun the tools people are expected to use every day.

Commercial Focus

Builds with revenue discipline, go-to-market clarity, and a strong bias toward practical outcomes.

Frontier Mindset

Works comfortably between established advertising systems and frontier technologies like blockchain and AI.

Selected Highlights

A track record built on repeated company creation and operator-led execution.

2013 Founded StreamRoll Media
2014 Launched VidRoll
2016 Started MetaX / adChain
2022 Founded AdPrompt

Media Coverage

Selected press and industry coverage across Ken Brook’s ventures.

Coverage has centered most visibly on MetaX and adChain, where Ken’s work on transparency, ad fraud, and blockchain-based advertising infrastructure earned attention across business and adtech media.

Forbes article image for MetaX blockchain coverage
Forbes 2017

How MetaX Plans To Use Blockchain To Stop Ad Fraud

A founder profile on Ken Brook and MetaX’s launch of adChain, framing the company’s push to bring more transparency to digital advertising.

MetaX / adChain Read coverage
WSJ The Wall Street Journal
The Wall Street Journal 2018

What’s an Online Ad Worth? Blockchain Might Help With That

Wall Street Journal coverage of how blockchain-based systems could improve trust, pricing, and accountability across digital advertising markets.

MetaX / adChain Read coverage
AdExchanger article image for MetaX coverage
AdExchanger 2017

Blockchain Is Bubbling Up As A Solution To The Supply Chain’s Transparency Woes

Industry coverage of MetaX’s early blockchain approach, including Ken’s perspective on how opaque supply chains weaken advertiser trust.

MetaX Read coverage
Adweek article image for blockchain advertising coverage
Adweek 2020

2 Years Ago, Blockchain Was Hyped as a World Changer. So What Happened?

Adweek revisited the blockchain wave in advertising and included Ken Brook and MetaX in its look at what the industry got right, what stalled, and what still mattered.

MetaX Read coverage
Digiday article image for blockchain advertising coverage
Digiday 2017

Why Digital Advertising Is Experimenting With Blockchain

Digiday highlighted MetaX and adChain as part of the broader movement to rethink verification, transparency, and fraud prevention in adtech.

MetaX / adChain Read coverage
MediaPost article image for Ken Brook coverage
MediaPost 2017

MetaX’s Brook On Web 3.0 Ad Serving

A commentary-driven feature focused directly on Ken Brook’s point of view about blockchain’s future role in programmatic media buying.

MetaX Read coverage
MarTech article image for MetaX blockchain whitelist coverage
MarTech 2018

MetaX Launches A Blockchain-Based Whitelist Of Websites

Coverage of MetaX’s adChain Registry initiative, expanding the company’s product narrative beyond fraud prevention into publisher quality and trust.

MetaX / adChain Registry Read coverage
SiliconANGLE article image for MetaX adChain coverage
SiliconANGLE 2017

MetaX Wields Blockchain In Bold Bid To Clean Up Digital Advertising

Startup and infrastructure-focused coverage on MetaX’s attempt to use blockchain as a foundational upgrade to the advertising ecosystem.

MetaX Read coverage

Videos

Featured video content connected to Ken Brook’s current work.

A growing set of founder, product, and company videos that give a more direct look at the mission, thinking, and market opportunities behind the ventures Ken is building.

YouTube In Time Tec

Agentic AI and Better Ads w/ Ken Brook | Trust, AI Agents & Marketing | Tech Talks Episode 10

A podcast-style conversation featuring Ken Brook on agentic AI, trust layers, and how advertising and marketing infrastructure evolves as autonomous systems become more capable.

Watch on YouTube
YouTube AdPrompt

Revolutionizing Local Marketing with AI Powered AdPrompt Agents

A product-focused look at how AdPrompt uses AI agents to help local businesses create, launch, and manage marketing with far less manual complexity.

Watch on YouTube
YouTube AdPrompt

AdPrompt.Ai Mission

A short mission-driven video introducing AdPrompt and the broader vision behind using AI to simplify campaign execution for businesses that need better marketing leverage.

Watch on YouTube

Venture Timeline

From adtech infrastructure to AI-powered growth platforms.

2013

StreamRoll Media

Founded during a wave of platform fragmentation, StreamRoll Media focused on helping marketers navigate cross-screen advertising more effectively.

2014

VidRoll

Built as a programmatic video monetization platform for premium publishers, with an emphasis on trading efficiency and stronger video revenue performance.

2016

MetaX / adChain

Helped pioneer blockchain-based advertising infrastructure through adChain, with an early focus on transparency, trust, and fraud resistance across the digital supply chain.

2022

AdPrompt

Founded AdPrompt to simplify campaign creation, optimization, and multichannel advertising execution through AI-driven automation for businesses with limited time and resources.

Current Focus

Making advanced marketing infrastructure usable for more businesses.

Ken’s current work at AdPrompt reflects the same throughline as his earlier ventures: reduce complexity, increase leverage, and build systems that help operators move faster. Today, that means applying AI to content generation, campaign decisioning, optimization, and multichannel advertising execution.

Ken builds where technical change is real, but the operating layer still needs to catch up.

This site is built as a concise professional overview for kgbrook.com.