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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UH receives $1M grant to advance research on rare pediatric disorder

peds research

The University of Houston has received a two-year, $1.1 million gift from the Cynthia and George Mitchell Foundation to advance research on a rare genetic disorder that can lead to both deafness and blindness in children, known as Usher Syndrome.

The current grant will support the research of UH biomedical engineering professors Muna Naash and Muayyad Al-Ubaidi, who work in the Laboratory for Retinal Molecular and Cellular Biology and Gene Therapy in the Cullen College of Engineering. The professors have published their findings in the journal Nature Communications.

Naash and Al-Ubaidi’s research focuses on mutations in the USH2A gene, which is crucial to the development and maintenance of the inner ear and retina. The work was inspired by a chance meeting that changed Naash’s life.

“Our work began more than two decades ago when I met a young boy who had lost his both his vision and hearing, and it made me realize just how precious those two senses are, and it truly touched my heart,” Naash said in a news release from UH. “Thanks to the generosity of the Cynthia and George Mitchell Foundation, we can now take the next critical steps in our research and bring hope to families affected by this challenging condition.”

The grant from the foundation comes in addition to a previous $1.6 million award from the National Eye Institute in 2023, which helped create a research platform for innovative gene therapy approaches for the condition.

Usher Syndrome affects 25,000 people in the U.S. and is the most common genetic condition worldwide that impacts both hearing and vision in children. Currently, there is no cure for any of the main three types of the condition. UH believes support from the Cynthia and George Mitchell Foundation will help elevate research, advance real-world solutions in health and improve lives.

“What makes UH such a powerful hub for research is not just its own resources, but also its location and strategic partnerships, including those with the Texas Medical Center,” Al-Ubaidi said in a news release. “We have access to an extraordinary network, and that kind of collaborative environment is essential when tackling complex diseases like Usher syndrome, where no single lab can do it alone.”

Members-only coworking club Switchyards to open first Houston location

Where to Work

An innovative take on the coworking space is coming to Houston. Switchyards will open its first location in the Bayou City on Monday, September 29.

Located in the former Buffalo Exchange at 2901 S Shepherd Drive, Switchyards is well located on the border of Montrose, River Oaks, and Upper Kirby. Founded in Atlanta, the Houston location will join 30 outposts in cities such as Austin, Dallas, Denver, Kansas City, and Nashville.

Unlike WeWork, which caters to companies looking for office space for groups of employees, Switchyards pitches itself as a club for individuals who want to get a little work done away from their home offices.

“Working from home all the time is pretty lonesome,” Switchyards creative director Brandon Hinman says. “It feels good to have places to get out and mix it up. To change paces and change scenery.”

Switchyards facilitates that change of scenery with an environment that blends touches of hotel lobbies, college libraries, and coffee shops. As seen in the photos of the company’s other location, the furniture is a mix of desks, comfy chairs, and couches for individuals or small groups. It’s a far cry from the cube farms of the Office Space era.

“They tend to be historic, textured, layered,” Hinman says about the company’s locations. “A lot of really good furniture. Really thoughtful for getting a couple hours of work done.”

Each location features fast wi-fi, plenty of electrical outlets, and good quality coffee and tea. All 250 members have 24/7 access to the space. And by choosing the real estate they lease carefully, Switchyards keeps its membership price to $100 per month.

“Packaging it together like that and opening in these neighborhoods where people actually live has been pretty magical,” Hinman says. "The big opportunity, I think, is that 90 percent of our members have never had a shared space before. It is unlocking a new thing for people.”

Those who are interested in learning more can sign up at switchyards.com/houston-tx to get early access to memberships and an invite to a sneak peek party.

Memberships go on sale Thursday, September 25 at 10 am. Switchyards notes that the last 14 clubs have sold out on day one.

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This story originally appeared on CultureMap.com.

Houston's surge in new startups cools since pandemic peak, study shows

by the numbers

Startup activity in the Houston metro area has dipped since its pandemic peak, according to a new study.

Dating back to 2005, the volume of applications to form new businesses in the Houston area hit its highest level in 2021 (151,804). Since then, though, the application volume has fallen, according to the study, conducted by business debt collection agency The Kaplan Group. Here's the breakdown from the last few years:

  • Applications dropped to 130,011 in 2022
  • Climbed to 145,926 in 2023
  • Dropped again to 138,595 in 2024

Looking at the Houston area’s figures another way, the 2024 total surpassed the 2015-19 average by roughly 60 percent to 90 percent, the study shows.

Dallas-Fort Worth has seen similar startup declines (162,312 in 2021 vs. 153,378 in 2024), but the San Antonio metro area recorded higher application volume in 2023 and 2024 (37,412 and 35,798, respectively) than it did in 2021 (34,208).

The story is different in the Austin metro area. Application volume in 2023 and 2024 (53,200 and 59,190, respectively) exceeded the 2021 total (47,106).

The picture for startup activity in Texas’ four major metros deviates from the nationwide picture.

“America’s real viral trend is entrepreneurship,” says The Kaplan Group. “New business formations are reaching an all-time high across the country.”

In the U.S., per-month business formations soared 435 percent from 2004 (89,561) to 2025 (478,805), the study says.

Amid the growth of startup activity, business bankruptcies in the U.S. have plummeted almost 74 percent since 2004, according to The Kaplan Group.

“The country’s business scene has grown both more resilient and more ambitious in the past two decades,” the collection agency says.

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