Houston founder shares how he's using tech to make digital media more effective and equitable

houston innovators podcast episode 173

This month, Mark Walker is celebrating his company's one year anniversary of going public — only the ninth Black-founded business to accomplish this feat on a U.S. stock exchange. Photo courtesy

After working in both sides of the advertising world, Mark Walker thought he could reimagine a platform that would be more efficient and equitable.

Walker co-founded his company, Direct Digital Holdings, an adtech platform, after serving in several roles — from an early hire at Houston digital media startup Questia to business development director at NRG Energy and COO of EBONY Media. He shares on the Houston Innovators Platform how he took this experience in tech, advertising, and media to create his company's platform.

"NRG Energy gave me a top-down view of the value chain, and Ebony gave me a bottoms-up view of the value chain of how media is purchased," Walker says on the show. "At Direct Digital Holdings, we help companies buy and sell media — and we leverage technology to do it. It's really the culmination of both of those experiences."

With over 30,000 publishers on its platform, Direct Digital makes it easier for its core customers — middle market companies looking to buy into the digital media ecosystem — to tap into these opportunities without the tech know-how they might otherwise need. Walker explains that at EBONY, he saw how small to midsize publications — especially the multicultural ones — were being left out on the ad selling side of the equation. The Direct Digital platform bridges the gap on each end.

Founded in 2018 in partnership with Keith Smith, who went through similar professional experiences, Direct Digital went public exactly one year ago after growing the company through strategic M&A activity. Walker says the decision to IPO made the most sense for his company — though it wasn't an easy process. Direct Digital is only the ninth company founded by a Black entrepreneur to go public on a US stock exchange.

"If you think the process is hard — it actually is," Walker says on the journey to IPO. "We were a privately held company, and we knew we had a good growth trajectory and we looked a couple different options. We decided to go public in a very traditional way."

Walker explains there were some risks involved, but the co-founders ultimately decided to shy away from adding in investors who might not have the same ideas for the company's future.

Direct Digital has been a Houston company from the star — despite the city not being home to a booming adtech ecosystem. Instead, Houston — with its collection of Fortune 500 companies and rich diversity — has allowed the business to stand out.

"If you look at and reflect on how our company has been built — from our board of directors to our leadership and management team — we're a majority minority organization all the way across the board," Walker says. "Diversity is very important to us. It's the lifeblood of our business — especially because we're serving publishers in those communities in big way. And moreso, we think you get the best product, thoughts, and ideas from a diverse workforce, and Houston fits right into that mold for us."

Walker shares more about his company's future, advice on IPO, and what all he's watching in adtech — from AI to streaming — on the podcast. Listen to the interview below — or wherever you stream your podcasts — and subscribe for weekly episodes.


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Austin company to bring AI-powered school to The Woodlands

AI education

Austin-based Alpha School, which operates AI-powered private schools, is opening its first Houston-area location in The Woodlands.

The 8,000-square-foot school, scheduled to be ready for the 2026-27 academic year, initially will serve students in kindergarten through eighth grade. Alpha says the school will offer “open workshop spaces and innovative classrooms that support personalized instruction, core academics, leadership development, and real-world life skills.”

Alpha sets aside two hours each school day for the AI-driven, self-paced study of core subjects like math, reading and science. The rest of each school day consists of life-skills workshops focusing on topics such as leadership and financial literacy.

Alpha’s school in The Woodlands has begun accepting applications for the 2026-27 school year. Annual tuition costs $40,000.

“The Woodlands is one of the most dynamic, forward-thinking communities in Texas, and Alpha is proud to bring

an innovative educational model that complements its strong academic foundation,” says Rachel Goodlad, head

of expansion for Alpha.

Founded in 2014, Alpha School combines adaptive technology-driven instruction with immersive life-skills workshops. Its model emphasizes mastery-based learning in core subjects alongside development of communication, critical thinking, financial literacy and leadership skills. It operates more than 15 schools across the country.

Elsewhere in Texas, Alpha operates schools in Austin, Brownsville, Fort Worth and Plano. Alpha also operates 12 Texas Sports Academy campuses in Texas, including locations in Houston, Pearland and Richmond, along with a NextGen Academy esports school in Austin, a school for gifted students in Georgetown, and lower-cost Nova Academy campuses in Austin and Bastrop.

Alpha has fans and critics. While supporters tout students’ high achievement rates, detractors complain about the high tuition and the AI-influenced depersonalization of education.

“Students and our country need to be in relationship with other human beings,” Randi Weingarten, president of the American Federation of Teachers, a teachers union, tells The New York Times. “When you have a school that is strictly AI, it is violating that core precept of the human endeavor and of education.”

Alpha co-founder MacKenzie Price, a podcaster and social media influencer, doesn’t share Weingarten’s views.

“Parents and teachers: We need to embrace this change,” Price wrote after President Trump signed an executive order promoting AI in schools.

The Times notes that Alpha doesn’t employ AI as a tutor or a supplement. Rather, the newspaper says, AI is “the school’s primary educational driver to move students through academic content.”

Houston space tech co. lands $175M and more innovation news to know

Trending News

Editor's note: The top Houston innovation news for the month includes major fundraising rounds for two Houston scaleups and local inductees into the National Academy of Inventors. Here are the five most-read InnovationMap headlines from March 1-15, 2026:

1. Intuitive Machines secures $175M equity investment to fuel growth

Intuitive Machines has landed a $175 million investment as it looks secure satellite deals and develop space-based data centers. Photo courtesy Intuitive Machines.

Houston-based space infrastructure and services company Intuitive Machines has secured a $175 million equity investment from unidentified institutional investors. The investors received shares of Class A stock in exchange for their funding. Publicly held Intuitive Machines (Nasdaq: LUNR) says it plans to use the capital to help build revenue and invest in technology, including communications and data-processing networks. Continue reading.

2. Houston e-commerce giant Cart.com raises $180M, surpasses $1B in funding

Cart.com has raised $180 million to scale its logistics network, expand AI capabilities and develop workflow automation tools. Photo courtesy of Cart.com

Houston-based commerce and logistics platform Cart.com has raised $180 million in growth capital from private equity firm Springcoast Partners, pushing the startup past the $1 billion funding mark since its founding in 2020. Cart.com says it will use the capital to scale its logistics network, expand AI capabilities and develop workflow automation tools. Continue reading.

3. Houston leads Texas with 7 new National Academy of Inventors senior members

The University of Houston has more faculty named to this year’s senior member class of the National Academy of Inventors than any other Texas institution. Photos courtesy UH.

The University of Houston is now home to seven new senior members of the National Academy of Inventors. According to UH, its seven new members represent the largest group from any single Texas institution this year, bringing the university's total senior member count to 46. Continue reading.

4. Booming Houston suburb launches innovation grant to attract startups

The City of Sugar Land is putting money on the table to support startups that relocate jobs to southwest Houston. Photo via Getty Images.

Think you’ve got a burgeoning startup? Consider moving it to southwest Houston. The City of Sugar Land announced the Sugar Land Starts Innovation Fund to support companies that move jobs to the area. Continue reading.

5. 6+ can't-miss Houston business and innovation events in March

From CERAWeek to H-Town Roundup, here's what not to miss this month and how to register. Photo courtesy of CERAWeek

March brings the return of some of Houston’s signature innovation events, plus insightful talks and celebrations in honor of Women's History Month. Here’s what not to miss and how to register. Continue reading.

Houston researcher secures $1.7M to develop drug for aggressive form of breast cancer

cancer research

A University of Houston researcher has joined a $3.2 million effort to develop a new drug designed to attack a cancer-driving protein commonly found in triple-negative breast cancer.

Triple-negative breast cancer (TNBC) is one of the most difficult-to-treat forms of cancer and accounts for 10 percent to 15 percent of all breast cancer cases. The disease gets its name because tumors associated with it test negative for estrogen receptors, progesterone receptors and excess HER2 protein, making it difficult to target. Due to this, TNBC is often treated with general chemotherapy, which can come with negative side effects and drug resistance, according to UH.

UH College of Pharmacy research associate professor Wei Wang is developing a drug that can target the disease more specifically. The drug will target MDM2, a protein often overproduced in TNBC that also contributes to faster tumor growth.

Wang is working on a team led by Wei Li, director of the University of Tennessee Health Science Center College of Pharmacy’s Drug Discovery Center. She has received $1.7 million to support the research.

Wang and UH professor of pharmacology and toxicology Ruiwen Zhang have discovered a compound that can break down MDM2. In early laboratory models, the compound has shown the ability to shrink tumors.

Wang and Zhang will focus on understanding how the treatment works and monitoring its effectiveness in models that closely mirror human disease.

“We will study how the drug targets MDM2 and evaluate the most promising drug candidates to determine effective dosing, understand how the drug behaves in the body, compare it with existing treatments and assess early safety,” Wang said in a news release.

Li’s team at the University of Tennessee will be working on the chemistry and drug design end of the project.

“This work could lead to an entirely new class of therapies for triple-negative breast cancer,” Li added in the release. “We’re hopeful that by directly removing the MDM2 protein from cancer cells, we can help more patients respond to treatment regardless of their tumor type.”

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