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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Houston space companies land $150M NASA contract for vehicles and robots

space simulations

Houston-based MacLean Engineering and Applied Technology Services LLC, known as METECS, has received a five-year contract from NASA to develop simulations and software services for space-based vehicles and robots, with a maximum value of $150 million.

Two other Houston-area companies, Tietronix Software Inc. and Vedo Systems LLC, were assigned as subcontractors for the award.

"This award is a strong testament to NASA’s continued trust in the quality of our work and their confidence in our ongoing support of the human spaceflight program," John MacLean, president of METECS said in a release.

According to NASA, the awardees are tasked with providing:

  • Simulation and software services for space-based vehicle models and robotic manipulator systems
  • Human biomechanical representations for analysis and development of countermeasure devices
  • Guidance, navigation, and control of space-based vehicles for all flight phases
  • Space-based vehicle on-board computer systems simulations of flight software systems
  • Astronomical object surface interaction simulation of space-based vehicles
  • Graphics support for simulation visualization and engineering analysis
  • Ground-based and onboarding systems to support human-in-the-loop training

The contract is called Simulations and Advanced Software Services II (SASS II), and begins in October. This is the second time METECS has received the SASS award. The first also ran for five years and launched in 2020, according to USASpending.gov.

METECS specializes in simulation, software, robotics and systems analysis. It has previously supported NASA programs, including Orion, EHP, HLS, Lunar Gateway and Artemis. It also serves the energy, agriculture, education and construction sectors.

Tietronix Software has won numerous awards from NASA. Most recently, it won the NASA JSC Exceptional Software Award (2017). Some of its other customers include Houston Independent School District, Baylor College of Medicine, DARPA and Houston Methodist.

Video Systems offers software for implementing human-rated, AI and autonomous systems, as well as engineering services to address the needs of spaceflight and defense. The company has previously worked with NASA and METECS, as well as Axiom Space and defense contractor Lockheed Martin.

The three companies are headquartered near NASA’s Johnson Space Center in Houston.

Greentown Labs names Lawson Gow as its new Houston leader

head of hou

Greentown Labs has named Lawson Gow as its Head of Houston.

Gow is the founder of The Cannon, a coworking space with seven locations in the Houston area, with additional partner spaces. He also recently served as managing partner at Houston-based investment and advisory firm Helium Capital. Gow is the son of David Gow, founder of Energy Capital's parent company, Gow Media.

According to Greentown, Gow will "enhance the founder experience, cultivate strategic partnerships, and accelerate climatetech solutions" in his new role.

“I couldn’t be more excited to join Greentown at this critical moment for the energy transition,” Gow said in a news release. “Greentown has a fantastic track record of supporting entrepreneurs in Houston, Boston, and beyond, and I am eager to keep advancing our mission in the energy transition capital of the world.”

Gow has also held analyst, strategy and advising roles since graduating from Rice University.

“We are thrilled to welcome Lawson to our leadership team,” Georgina Campbell Flatter, CEO of Greentown Labs, added in the release. “Lawson has spent his career building community and championing entrepreneurs, and we look forward to him deepening Greentown’s support of climate and energy startups as our Head of Houston.”

Gow is the latest addition to a series of new hires at Greentown Labs following a leadership shakeup.

Flatter was named as the organization's new CEO in February, replacing Kevin Dutt, Greentown’s interim CEO, who replaced Kevin Knobloch after he announced that he would step down in July 2024 after less than a year in the role.

Greentown also named Naheed Malik its new CFO in January.

Timmeko Moore Love was named the first Houston general manager and senior vice president of Greentown Labs. According to LinkedIn, she left the role in January.

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This article originally appeared on our sister site, EnergyCapitalHTX.com.

Houston foundation grants $27M to support Texas chemistry research

fresh funding

Houston-based The Welch Foundation has doled out $27 million in its latest round of grants for chemical research, equipment and postdoctoral fellowships.

According to a June announcement, $25.5 million was allocated for the foundation's longstanding research grants, which provide $100,000 per year in funding for three years to full-time, regular tenure or tenure-track faculty members in Texas. The foundation made 85 grants to faculty at 16 Texas institutions for 2025, including:

  • Michael I. Jacobs, assistant professor in the chemistry and biochemistry department at Texas State University, who is investigating the structure and thermodynamics of intrinsically disordered proteins, which could "reveal clues about how life began," according to the foundation.
  • Kendra K. Frederick, assistant professor in the biophysics department at The University of Texas Southwestern Medical Center, who is studying a protein linked to Parkinson’s disease.
  • Jennifer S. Brodbelt, professor in chemistry at The University of Texas at Austin, who is testing a theory called full replica symmetry breaking (fullRSB) on glass-like materials, which has implications for complex systems in physics, chemistry and biology.

Additional funding will be allocated to the Welch Postdoctoral Fellows of the Life Sciences Research Foundation. The program provides three-year fellowships to recent PhD graduates to support clinical research careers in Texas. Two fellows from Rice University and Baylor University will receive $100,000 annually for three years.

The Welch Foundation also issued $975,000 through its equipment grant program to 13 institutions to help them develop "richer laboratory experience(s)." The universities matched funds of $352,346.

Since 1954, the Welch Foundation has contributed over $1.1 billion for Texas-nurtured advancements in chemistry through research grants, endowed chairs and other chemistry-related ventures. Last year, the foundation granted more than $40.5 million in academic research grants, equipment grants and fellowships.

“Through funding basic chemical research, we are actively investing in the future of humankind,” Adam Kuspa, president of The Welch Foundation, said the news release. “We are proud to support so many talented researchers across Texas and continue to be inspired by the important work they complete every day.”

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