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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Rice University to lead AI conferences in Paris this spring and summer

where to be

Houston’s own Rice University will host a series of conferences on artificial intelligence in Paris, France, starting this month. The series will tackle the impact and possibilities of AI in fields like econometrics and online privacy security.

“Artificial intelligence is transforming the global economy and raising profound questions about how technology intersects with society,” Caroline Levander, Rice’s vice president for global strategy, said in a news release. “By convening scholars from multiple disciplines and countries in Paris, Rice is helping shape the international conversation about how AI should be developed, governed and used.”

The four conferences in Paris aim for a multi-disciplinary approach that tackles aspects of AI from diverging angles. The conferences come as part of Rice’s increased partnership with French researchers at the Université Paris Sciences & Lettres. The two institutions have formed a binary star system of academic sharing and support.

“Paris has quickly become one of the most important global hubs for artificial intelligence research, entrepreneurship and policy,” Levander said. “For Rice, having a presence in the city allows our scholars to engage directly with that ecosystem while building collaborations that connect Europe and the United States around the future of AI.”

The conferences will be held at the Rice Global Paris Center. Topics scheduled are:

Emerging Topics in Operations Management: Platforms, Blockchains and AI

April 27-29

This conference will focus on how companies like Uber, Airbnb, Spotify, and DoorDash can use blockchain ledgers to deliver goods and services more transparently. It will also look at tokenized incentives, presumably forms of cryptocurrency and non-fungible tokens in the app space.

Econometrics and AI

May 5-7

This conference will explore how AI can be used in various economic statistical models and practices.

Human Flourishing in the Age of AI

June 3-5

This conference will be a collaboration between engineers and philosophers about the ethics and impact of AI on the lives of its users.

On the Crossroads of AI and Society: Incentives, Privacy and Fairness

July 15-16

This conference will consider how to stakeholders can ensure AI’s actions most benefit people, particularly in the fields of healthcare education, energy and public policy.

Houston claims 19% of Texas’ new live-work-play growth

by the numbers

In Texas, Houston is a big player in the live-work-play real estate movement.

A new 21-city analysis from coworking marketplace CoworkingCafe shows the Houston area added five live-work-play projects—mixed-use developments with residential, office and recreational components—over the past decade.

From 2016 to 2025, Houston accounted for 19 percent of Texas’ new live-work-play inventory, the analysis shows. Among the new local developments were Arrive Upper Kirby, St. Andrie, and The Laura:

Arrive Upper Kirby, which was sold in 2021 for $182 million, offers more than 61,000 square feet of retail and restaurant space adjacent to apartments and offices. The 13-story, 265,000-square-foot project was completed in 2017.
St. Andrie, a 32-acre, mixed-use community, was completed in 2019. The apartment-anchored development includes an H-E-B grocery store and 37,000 square feet of office space.
The Laura, spanning 110,000 square feet, was completed in 2023. Among the apartment complex’s amenities is a coworking space.

According to Northspyre, a software provider for real estate developers, live-work-play projects enable people to meet their needs, such as housing, workplaces, stores, restaurants, and recreation facilities, in a single place.

A total of 542 live-work-play developments opened between 2016 and 2025 in the 21 cities, with another 69 in the pipeline for 2026, CoworkingCafe says. Among major markets, New York City made up the largest share (119) of new live-work-play developments from 2016 to 2025.

The Houston area’s five projects were built in 2018, 2019, 2020, 2024, and 2025, CoworkingCafe data indicates, with another project scheduled for completion next year. The Greater Houston Partnership recently highlighted four mixed-use projects taking shape in the region, but only one of them is scheduled to be finished in 2027. It can take two to five years or more to complete a mixed-use development.

Of the five Houston developments finished in the past decade, 56 percent of the space went toward multifamily units, 29 percent toward offices, and 16 percent toward retail, CoworkingCafe says.

As noted by the Houston-Galveston Area Council, economic development in the 21st century “is about cultivating quality live-work-play environments that attract, retain, and grow a diverse and skilled population. Employers and businesses are increasingly choosing to make long-term investments in places that connect and engage people to strengthen economic competitiveness and promote innovation.”

With eight completed projects, Austin led construction of live-work-play developments in Texas from 2016 to 2025, according to CoworkingCafe. Dallas, which welcomed five live-work-play developments during that period, tied with Houston. San Antonio data wasn’t available.

Rice Business Plan Competition awards $1.4M to 2026 student teams

winner, winners

Editor's note: This article has been updated to correct the total amount of investment and cash prizes awarded at the RBPC and with additional information from Rice.

Another team from the Great Lakes State took home top honors and investments at this year's Rice Business Plan Competition.

BRCĒ, a material-tech startup from Michigan State University, took home the top-place finish and the largest investment total at the annual Houston event. It has developed Lattice-Grip technology to create utility-based polymers that can replace traditional fabric. The materials are stronger, fire-resistant and more stable than traditional textiles, according to the company. Last year, the University of Michigan's Intero Biosystems won first-place finish and the largest investment total of $902,000.

In total, the RBPC doled out more than $1.4 million in investment and cash prizes, according to Rice. Over the three-day event, held April 9-11, the 42 competing startups presented their business plans to 300 angel, venture capital and corporate investors. Seven finalists were selected.

Three Texas teams, including one from Houston, were named among the finalists. Here's who won big this year, with their investment totals and some of their awards listed below.

BRCĒ, Michigan State University — $611,500

The recent Shark Tank alum finished in first place for its utility-based polymers technology.

$200,000 Goose Capital Investment Grand Prize
$100,000 The OWL Investment Prize
$100,000 Houston Angel Network Investment Prize
$75,000 The Indus Entrepreneurs (TiE) Texas Angels Investment Prize
$50,000 nCourage Investment Network’s Courageous Women Entrepreneur Investment Prize
$25,000 New Climate Ventures Sustainable Investment Prize
$20,000 Aramco Innovator Cash Prize
$1,000 Anbarci Family Company Showcase Prize
$500 Mercury Fund Elevator Pitch Competition Prize – Consumer Hard Tech

Legion Platforms, Arizona State University — $535,500

The startup won second place for its multiplayer gaming platform that can be accessed with slow internet speeds.

$100,000 Anderson Family Fund & Finger Interests Second Place Investment Prize
$200,000 Goose Capital Investment Prize
$100,000 The OWL Investment Prize
$25,000 Pearland EDC Spirit of Entrepreneurship Cash Prize
$500 Mercury Fund Elevator Pitch Competition Prize – Consumer

Imagine Devices, University of Texas at Austin — $111,000

The pediatric medical device company won third place for its multifunction neonatal feeding tube, known as Trinity Tube

$50,000 Anderson Family Fund & Finger Interests Third Place Investment Prize
$25,000 Pearland EDC Spirit of Entrepreneurship Cash Prize
$25,000 The Eagle Investors Investment Prize
$1,000 Anbarci Family Company Showcase Prize

Altaris MedTech, University of Arkansas – $16,000

The startup won fourth place for its pain-free strep test.

$5,000 Norton Rose Fulbright Fourth Place Prize
$1,000 Mercury Fund Elevator Pitch Competition Prize — Overall Winner

Routora, University of Notre Dame & University of Texas at Austin – $15,500

The team won fifth place for its route optimization app that works to reduce fuel costs, travel time and carbon emissions

$5,000 Chevron Fifth Place Prize
$500 Mercury Fund Elevator Pitch Competition Prizes — Digital

DialySafe, Rice University — $15,500

The startup won sixth place for its technology that aims to make at-home peritoneal dialysis simpler and safer.

$5,000 ExxonMobil Sixth Place Prize
$500 Mercury Fund Elevator Pitch Competition Prizes — Life Science

Arrow Analytics, Texas A&M University – $16,000

The startup won seventh place for its AI-powered sizing system for carry-on baggage.

$5,000 Shell Ventures Seventh Place Prize
$1,000 Anbarci Family Company Showcase Prizes

Other significant prizes included:

BiliRoo, University of Michigan – $26,000

$25,000 Southwest National Pediatric Device Consortium Pediatric Device Cash Prize
$1,000 Anbarci Family Company Showcase Prizes

BeamFeed, City University of New York – $25,000

$25,000 Amentum and WRX Companies Rising Stars Space Technology and Commercial Aerospace Cash Prize

Grapheon, University of Pittsburgh — $20,000

$20,000 Aramco Innovator Cash Prize

A total of $75,000 in in-kind legal services was awarded to all finalists. The grand prize winner, BRCĒ, also received a chief financial officer consulting prize worth $40,000. Each competing startup received at least $950 in prizes for placement in the competition.

“The Rice Business Plan Competition has grown into far more than a competition—it’s a proving ground for founders and a catalyst for real company formation, as well as a catalyst for building the Houston entrepreneurial ecosystem,” Brad Burke, associate vice president of Rice Innovation and executive director of Rice Alliance, said in a news release. This year's event was Burke’s final RBPC after nearly 25 years of leadership.

Last year, the Rice Business Plan Competition facilitated over $2 million in investment and cash prizes. According to Rice, more than 910 startups have raised more than $6.9 billion in capital through the competition over the last 25 years.

See a full list of this year's winners and stream rounds from the competition here.

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