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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Energy AI company opens first U.S. office at Houston’s the Ion

Building on its partnership with Houston-based oilfield services provider Halliburton, energy-sector AI company Shape Digital recently opened an office at The Ion. It’s the company’s first U.S. location.

Shape Digital’s workforce in Houston includes employees specializing in tech support, business development and client services. The company’s local hiring projections and headcount weren’t available. The new office will be located within Industrious at the Ion, according to Rice Alliance.

A key driver of the new Houston office: The company forecasts North America will account for more than 20 percent of its business in 2027.

“North America is a critical market for industrial innovation, and Houston sits at the center of companies driving that progress,” Caio Sene, vice president of client services at Shape Digital, said in a release. “Growing our presence here allows us to work alongside operators as they look for practical ways to turn existing operational data into clear recommendations for what to do next.”

Shape Digital, which also has offices in Singapore and Brazil, develops decision-making platforms for the oil and gas sector.

The Ion District office gives Shape Digital a presence close to Halliburton’s headquarters. In May, the two companies forged a partnership to combine Halliburton’s Digital Field Solverdecision-making system with Shape Digital’s AI portfolio.

Shape Digital layers AI software atop existing operations data rather than replacing legacy systems or adding new software.

The company’s suite of AI agents draws on more than 200 operations-monitoring algorithms, continually learning from company and industry data. The suite comprises four products: Shape Aura, Shape Lighthouse, Shape Lumen and Shape Reef.

Shape Digital says that by working with a customer’s existing operations data, it can deliver ROI in less than two months without any additional investment in equipment or infrastructure.

The company is a 2021 spinoff of Japan-based Modec. Modec builds, owns, and operates floating offshore oil and gas production facilities. Its Modec America subsidiary is based in Houston.

Meet the esteemed judges for the 2026 Houston Innovation Awards

Meet The Judges

Editor's note: Judging is now underway for the 2026 Houston Innovation Awards, and it's time to meet the decision makers.

Our 2026 judging panel comprises past award winners who represent a variety of industries and areas of expertise. They are joined by InnovationMap's interim editor. All are deeply engaged in the Houston innovation ecosystem.

Our judging panel will review all nominee applications submitted across 10 prestigious categories. They will determine the 2026 finalists in all categories, and they will select the winners in all but one category — our people's choice award for Startup of the Year.

The sixth annual Houston Innovation Awards program will be presented in an all-digital format in 2026. We will announce this year's finalists and feature their stories throughout our special editorial series this fall. Then, stay tuned as we reveal the 2026 Houston Innovation Awards winners on InnovationMap.com in mid-November.

Sagar Dalal, Fervo Energy, 2025 Scaleup of the Year

Sagar Dalal serves as chief of staff at Fervo Energy, a company pioneering the commercialization of next-generation geothermal power. In this role, he helps translate the CEO’s vision and priorities into execution, leading cross-functional strategic initiatives that support the company’s growth and operations.

Dalal brings nearly eight years of experience in structural engineering and project management from his time at Thornton Tomasetti and Tesla, where he engineered and built a wide range of infrastructure projects ranging from stadiums to manufacturing facilities. He holds an MBA from Stanford University and an MS in Civil Engineering from Texas A&M University. He is also a licensed professional engineer.

Aaron Fitzgerald, Mars Materials, 2025 Minority-founded Business of the Year

Aaron Fitzgerald is a three-time founder and carbon removal entrepreneur focused on reimagining how we make things. As the CEO of Mars Materials, he leads a team working to commercialize technologies that sequester captured carbon into industrial supply chains.

His vision for a defossilized future is shaped by a unique path through both policy, including a tenure in the United States Senate, and deep carbontech, with fellowships at The Lewis Latimer program, Breakthrough Energy, Prime Coalition, and Carbon 180.

Tatiana Fofanova, Koda Health, 2025 Health Tech Business of the Year

Tatiana Fofanova, PhD, is the co-founder and CEO of Koda Health, an AI-enhanced patient decision support platform designed to make advance care planning (ACP) scalable, accessible, and patient-centered for patients with serious illness.

After earning her PhD in Translational Medicine at Baylor College of Medicine, she joined Texas Medical Center (TMC) as a Founder-in-Residence. It was there that she and her co-founders identified one of the most overlooked yet critical gaps in healthcare: the lack of meaningful, accessible advance care planning. Under her leadership, Koda Health now supports over 1 million patients through partnerships with organizations like Cigna, Privia, and Houston Methodist.

Lawson Gow, Greentown Labs, 2025 Incubator/Accelerator of the Year

Lawson Gow currently serves as chief strategy officer for Greentown Labs, which was named Incubator/Accelerator of the Year in the 2025 Houston Innovation Awards. Prior to joining Greentown Labs as Head of Houston in 2025, Gow was as a managing partner at Helium Capital, an investment and advisory firm that aims to support founders across the entire lifecycle of entrepreneurship.

He is also the founder of The Cannon, an innovation-infrastructure provider that operates a growing network of innovation hubs for its community of startups, entrepreneurs, investors, and corporate innovators.

Sarah Hein, March Biosciences, 2025 Female-founded Business of the Year

Sarah Hein is the founding CEO of March Biosciences, a clinical-stage cell-therapy company targeting challenging malignancies. Prior to cofounding March Biosciences, she was the founding Entrepreneur in Residence for the Texas Medical Center Innovation Accelerator for Cancer Therapeutics (TMCi ACT).

Formerly, she was a cofounder and the vice president of operations at Courier Therapeutics, a cancer immunotherapy startup acquired by Valo Health. She was also director of research at Resonant Therapeutics, an antibody therapeutics platform technology company. She began at Mercury Fund as a Venture Fellow directly after graduating with her PhD in Molecular Biology from Baylor College of Medicine.

Tanu Jain, FlowCare, 2025 Startup of the Year

Tanu Jain is a product executive, entrepreneur, founder and CEO of FlowCare, and registered nurse with a track record of building products from zero to global scale. She previously led product at BioIQ before founding FlowCare, a Houston-based period care infrastructure platform making period care a standard in every restroom. In under 16 months, FlowCare has signed deployed across four enterprise customers and impacted more than 1.5 million women.

FlowCare was named Startup of the Year at the 2025 Houston Innovation Awards, and Jain has been recognized with additional honors including the SDG Super Changemaker – Pewter — at the Global Sustainability Awards 2026.

Prabhdeep "Prab" Sekhon, Eclipse Energy, 2025 Energy Transition Business of the Year

Prabhdeep Singh Sekhon is CEO of Eclipse Energy, an energy technology company transforming depleted oil fields into low-cost, sustainable hydrogen resources through subsurface biotechnology. He brings nearly two decades of global energy experience spanning climate technology, venture capital, private equity, and multi-billion-dollar energy projects across five continents.

Previously, he held leadership roles at NextEra Energy Resources and Hess Corporation. He is also a founder and managing director of GreenLite Resources and a founding member of Cotogna Sports Group. He holds an MBA from Wharton, a Masters in Engineering from Texas A&M, and a BS from the University of Calgary.

Wade Pinder, Product Houston, 2025 Trailblazer Award Winner

Wade Pinder thinks of himself as an "ecosystem wayseeker," helping founders and builders in and around Houston find their footing, understand the landscape, and move through uncertainty with more clarity. Through Product Houston, he works at the intersection of product strategy, founder support, ecosystem mapping, and community-building, with a particular focus on helping people show up in the right rooms before they feel fully ready.

His background includes years in product management at Blinds.com and Home Depot, along with founding and leading the Houston Product Community for six years. He was recognized by as Mentor of the Year in the 2023 Houston Innovation Awards and received the Trailblazer Award in 2025.

Laura Furr Mericas, Interim Editor, InnovationMap

Laura Furr Mericas is interim editor for InnovatonMap.com and EnergyCapitalHTX.com. She is a longtime contributor to both sites and has reported on Houston's innovation ecosystem for InnovationMap since 2020. Previously, she served as web editor and data reporter for Houston Business Journal.

Report: Income for top 1 percent earners in Texas has surged in 2026

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In a state where local billionaires are wealthier than they've ever been, high-earning Texans need to make $73,000 more than they did a year ago if they want to be among the top 1 percent of earners, a new report has revealed.

SmartAsset's study analyzed income thresholds for the top 1, 5, and 10 percent of earners in all 50 states and the District of Columbia, using 2022 IRS data for individual tax return filers (the most recent year available), adjusted to 2026 dollars.

Texas has the 11th highest income threshold, with residents needing to make a minimum of $817,158 to be considered among the top 1 percent of earners statewide. In 2025, Texans needed to make about $744,000 to be among the top 1 percent.

For comparison, residents living in the nation's capital must make at least $1.16 million to qualify as top 1 percent earners. The District of Columbia led the nation with the highest income threshold to be a top earner.

To be considered among the top 5 percent of earners in Texas, a resident would need to make $312,671. The income threshold to be considered among the top 10 percent is $210,609.

SmartAsset additionally found that 128,130 Texas residents qualified as top 1 percent earners in 2022. Nationally, the report estimated that fewer than 2 million households earn enough to be considered among the top 1 percent of earners nationwide, but 23 million households rank among the top 10 percent.

"In some places, households can enter the top 1 percent at income levels that fall well below the threshold elsewhere, reflecting an uneven landscape of wages and wealth," the report said.

A separate SmartAsset study that tracked the upper and lower thresholds for middle class households found Houston residents need to make anywhere from $42,907 to $128,722 to maintain their middle class status.

The top 10 states with the highest thresholds to be considered in the top 1 percent of earners in the U.S. are:

No. 1 – District of Columbia ($1,156,664)
No. 2 – Connecticut ($1,147,898)
No. 3 – Massachusetts ($1,006,921)
No. 4 – California ($987,325)
No. 5– New Jersey ($969,976)
No. 6 – New York ($959,562)
No. 7 – Florida ($956,449)
No. 8 – Washington ($903,303)
No. 9 – Colorado ($828,772)
No. 10 – Wyoming ($819,014)

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This article originally appeared on CultureMap.com.

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