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 scientist launches new app to support mental health professionals

App for that

One Houston-based mental health scientist is launching a new app-based approach to continuing education that she hopes will change the way doctors, therapists, and social workers evolve in their field.

The app, MHNTI, is named for its parent company, the Mental Health Network & Training Institute. It's a one-stop shop for mental health professionals to find trainers, expert consultations, local providers, webinars, and other tools related to licensure certification and renewal.

Free and paid tiers offer different levels of access, but both offer doctors, counselors, and more an easier way to engage with continuing education. When a mental health professional is looking to expand their knowledge in a way that coincides with CE requirements, MHNTI provides it; as easy as using Amazon.

"We built MHNTI for the clinicians craving meaningful, ongoing training that fits real-life schedules," said Dr. Elizabeth McIngvale. "MHNTI is more than an app. It's a movement to support mental health professionals at every career stage."

McIngvale, the daughter of celebrated Houston entrepreneur Jim "Mattress Mack" McIngvale, co-founded MHNTI after becoming one of the leading experts on obsessive-compulsive disorder (OCD) in the United States. Born with the condition herself, she suffered greatly as a child to the point that she required extensive repetitive rituals daily just to function. She responded to exposure with response prevention (ERP) treatment, earned her Ph.D. from the University of Houston, and is now the director at the OCD Institute of Texas.

This is not the first time she used the internet to try to improve the mental health industry. In 2018, she launched the OCD Challenge website, a free resource for people with OCD.

McIngvale's co-founder is New York-based doctor, entrepreneur, and author Lauren Wadsworth, another expert in OCD and other anxiety disorders. Like McIngvale, she understands that the labyrinthian world of continuing education can keep mental health professionals from achieving their potential.

"Mental health providers are often overworked and under-resourced. MHNTI is here to change that," said Wadsworth. "We're creating a space where clinicians can continuously learn, grow, and feel supported by experts who understand the work firsthand."

MHNTI is available in the App Store, Google Play, and for desktop.

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A version of this article originally appeared on CultureMap.com.

Announcing the 2025 Houston Innovation Awards finalists

Inspirational Innovators

InnovationMap is proud to reveal the finalists for the 2025 Houston Innovation Awards.

Taking place on November 13 at Greentown Labs, the fifth annual Houston Innovation Awards will honor the best of Houston's innovation ecosystem, including startups, entrepreneurs, mentors, and more.

This year's finalists were determined by our esteemed panel of judges, comprised of past award winners and InnovationMap editorial leadership.

The panel reviewed nominee applications across 10 prestigious categories to determine our finalists. They will select the winner for each category, except for Startup of the Year, which will be chosen by the public via online voting launching later this month.

We'll announce our 2025 Trailblazer Award recipient in the coming weeks, and then we'll unveil the rest of this year's winners live at our awards ceremony.

Get to know all of our finalists in more detail through editorial spotlights leading up to the big event. Then, join us on November 13 as we unveil the winners and celebrate all things Houston innovation. Tickets are on sale now — secure yours today.

Without further ado, here are the 2025 Houston Innovation Awards finalists:

Minority-founded Business

Honoring an innovative startup founded or co-founded by BIPOC or LGBTQ+ representation:

  • Capwell Services
  • Deep Anchor Solutions
  • Mars Materials
  • Torres Orbital Mining (TOM)
  • Wellysis USA

Female-founded Business

Honoring an innovative startup founded or co-founded by a woman:

  • Anning Corporation
  • Bairitone Health
  • Brain Haven
  • FlowCare
  • March Biosciences
  • TrialClinIQ

Energy Transition Business

Honoring an innovative startup providing a solution within renewables, climatetech, clean energy, alternative materials, circular economy and beyond:

  • Anning Corporation
  • Capwell Services
  • Deep Anchor Solutions
  • Eclipse Energy
  • Loop Bioproducts
  • Mars Materials
  • Solidec

Health Tech Business

Honoring an innovative startup within the health and medical technology sectors:

  • Bairitone Health
  • Corveus Medical
  • FibroBiologics
  • Koda Health
  • NanoEar
  • Wellysis USA

Deep Tech Business

Honoring an innovative startup providing technology solutions based on substantial scientific or engineering challenges, including those in the AI, robotics and space sectors:

  • ARIX Technologies
  • Little Place Labs
  • Newfound Materials
  • Paladin Drones
  • Persona AI
  • Tempest Droneworx

Startup of the Year (People's Choice)

Honoring a startup celebrating a recent milestone or success. The winner will be selected by the community via an online voting experience:

  • Eclipse Energy
  • FlowCare
  • MyoStep
  • Persona AI
  • Rheom Materials
  • Solidec

Scaleup of the Year

Honoring an innovative later-stage startup that's recently reached a significant milestone in company growth:

  • Coya Therapeutics
  • Fervo Energy
  • Koda Health
  • Mati Carbon
  • Molecule
  • Utility Global

Incubator/Accelerator of the Year

Honoring a local incubator or accelerator that is championing and fueling the growth of Houston startups:

  • Activate
  • Energy Tech Nexus
  • Greentown Labs
  • Healthtech Accelerator (TMCi)
  • Impact Hub Houston

Mentor of the Year

Honoring an individual who dedicates their time and expertise to guide and support budding entrepreneurs. Presented by Houston Community College:

  • Anil Shetty, Inform AI
  • Jason Ethier, EnergyTech Nexus
  • Jeremy Pitts, Activate
  • Joe Alapat, Liongard
  • Neal Dikeman, Energy Transition Ventures
  • Nisha Desai, Intention

Trailblazer Recipient

  • To be announced
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Interested in sponsoring the 2025 Houston Innovation Awards? Contact sales@innovationmap.com for details.

Houston scientists earn prestigious geophysics career awards

winner, winner

Two Rice University professors have been recognized by the American Geophysical Union, one of the world’s largest associations for Earth and space science.

Rice climatologist Sylvia Dee was awarded the 2025 Nanne Weber Early Career Award by the AGU’s Paleoceanography and Paleoclimatology Section. Richard Gordon, a Rice professor of geophysics also received the 2025 Walter H. Bucher Medal by the AGU. They will both be recognized at the AGU25 event on Dec.15-19 in New Orleans.

The Nanne Weber Early Career Award recognizes contributions to paleoceanography and paleoclimatology research by scientists within 10 years of receiving their doctorate.

“Paleoclimate research provides essential context for understanding Earth’s climate system and its future under continued greenhouse warming," Dee said in a news release. “By studying how climate has evolved naturally in the past, we can better predict the risks and challenges that lie ahead.”

Dee’s work explores how Earth’s natural modes of variability interact with the changing climate and lead to extreme weather. It shows how these interactions can add to climate risks, like flooding and rainfall patterns all around the world.

The Bucher Medal is awarded to just one scientist for their original contributions to the knowledge of the Earth’s crust and lithosphere.

Gordon’s research has reshaped how scientists understand the movement and interaction of Earth’s tectonic plates. He helped reveal the existence of diffuse plate boundaries—areas where the planet’s crust slowly deforms across broad regions instead of along a single fault line. His work also explored true polar wander, a phenomenon in which Earth gradually shifts its orientation relative to its spin axis.

Gordon introduced the concept of paleomagnetic Euler poles, a method for tracing how tectonic plates have moved over millions of years. He also led the development of major global plate motion models, including NUVEL (Northwestern University Velocity) and MORVEL (Mid-Ocean Ridge Velocity).

“Receiving the Walter Bucher Medal is a profound honor,” Gordon said in a news release. “To be included on a list of past recipients whose work I have long admired makes this recognition especially meaningful. There are still countless mysteries about how our planet works, and I look forward to continuing to explore them alongside the next generation of scientists.”