Should your startup opt for SAFEs or convertible notes on your next funding round? This Houston expert weighs in. Photo via Getty Images

As both a founder and occasional early-stage investor in the Houston ecosystem, I've seen firsthand the opportunities and challenges surrounding seed funding for local startups. This critical first fundraising round sets the trajectory, but navigating the landscape can be tricky, especially for first time founders who may not be familiar with the lingo.

One key dynamic is choosing the right deal structure — SAFEs (Simple Agreement for Future Equity) vs. convertible notes are the most common vehicles early stage startups use to raise capital and are far more founder-friendly than a priced round.

Let's start first with what the have in common:

  • Both allow you to defer setting a valuation for your company until a later (likely priced) round, which is useful in early stages or pre-revenue companies
  • Both are cheaper and faster to execute than a priced round, which cash-strapped early stage founders like
  • Both can have terms like valuation cap, discount, conversion event, and pro rata rights.
  • Both are less attractive to investors seeking immediate equity (especially important if starting the QSBS clock is part of your investors strategy or if the investor is newer to startup investing)
  • Both can create messy cap tables and the potential for a lot of dilution for the founders (and investors) if they are used for multiple raises (especially with different terms)

While as you can see they have similarities, they have some important differences. Let's dig in on these next:

SAFEs:

  • Created by Y Combinator in 2013, the intent was to create a simplified, founder friendly agreement as an alternative to the convertible note
  • Is an agreement for future equity for the investor at a conversion event (priced round or liquidation event) which converts automatically.
  • It's not a debt instrument and does not accrue interest or have a maturity date.
  • Generally have much lower upfront legal costs and faster to execute

Convertible Notes:

  • A debt agreement that converts to equity at a later date (or conversion event like a priced round)
  • Accrues interest (usually 2 to 8 percent) and has a maturity date by which the note must either be repaid or convert to equity. If you reach your maturity date before raising a qualifying round, you can often renegotiate to extend the maturity date or convert the note, though be prepared to agree to higher interest rates, additional warrants, or more favorable conversion terms.
  • More complex and take longer to finalize due to non-standard terms resulting in higher legal and administrative costs

It's worth reiterating that in both cases, raising multiple rounds can lead to headaches in the form of complex cap tables, lots of dilution, and higher legal expenses to determine conversion terms. If your rounds have different terms on discounts and valuation caps (likely) it can cause confusion around equity and cap table structure, and leave you (the founder) not sure how much equity you will have until the conversion occurs.

In my last startup, our legal counsel — one of the big dogs in this space for what it's worth — strongly advised us to only do one SAFE round to prevent this.

Why do some investors tend to prefer convertible notes?

There are a few reasons why some investors, particularly angel investors from developing startup ecosystems (like Houston), prefer convertible notes to SAFEs.

  • Because they are structured as debt, note holders have a higher priority than equity investors in recovering their investment if the company fails or is liquidated. This means they would get paid after other creditors (like loans or credit cards) but before equity investors, increasing the likelihood of getting some of their money back.
  • The interest terms protect investors if the founder takes a long time to raise a priced funding round. As time passes, interest accumulates, increasing the investor's potential return. This usually results in the investor receiving a larger equity stake when the note converts. However, if the investor chooses to call in the note instead, the accrued interest would increase the amount of money owed, similar to a traditional loan
  • More defined conversion triggers (including a maturity date) gives investors more control and transparency on when and how their investment will convert.
  • Can negotiate more favorable terms than the standard SAFE agreement, including having both a valuation cap and a discount (uncommon on a SAFE, which usually only has one or the other), interest rates, and amendment clauses to protect them from term revisions on earlier investors by future investors (called a cram-down), etc.
We'll go over what the various terms in these agreements are and what to look out for in a future article

How to choose:

  • Consider your startup's stage and valuation certainty — really uncertain or super early? Either of these instruments are preferable to a priced round as you can defer the valuation discussion
  • Assess investor preferences in your network — often the deciding factor if you don't have a lot of leverage; most local angels prefer c-notes because they see them as less risky though SAFEs are becoming more common with investors in tech hubs like Silicon Valley
  • Evaluate your timeline and budget for legal costs — as I mentioned, SAFEs are way less expensive to execute (though still be prepared to spend some cash).
  • Align the vehicle with your specific goals and growth trajectory

There's no one-size-fits-all solution, so it's crucial to weigh these factors carefully.

The meanings of these round terms like "seed" are flexible, and the average seed funding amount has increased significantly over the past decade, reaching $3.5 million as of January 2024. This trend underscores the importance of choosing the right funding vehicle and approach.

Looking ahead, I'm bullish on Houston's growing startup ecosystem flourishing further. Expect more capital formation from recycled wins, especially once recently minted unicorns like High Radius, Cart.com, Solugen, and Axiom Space exit and infuse the ecosystem with fresh and hungry angels, new platforms beyond traditional venture models, and evolving founder demographics bringing fresh perspectives.

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Adrianne Stone is the principal product manager at Big Cartel and the founder of Bayou City Startups, a monthly happy hour organizer. This article original ran on LinkedIn.

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UTHealth Houston officially opens new tower in TMC's Helix Park

open for innovation

UTHealth Houston School of Public Health recently opened its new state-of-the-art tower in the Texas Medical Center’s Helix Park.

The 350,000-square-foot, 10-story campus at 1930 Old Spanish Trail was celebrated with an official ribbon-cutting ceremony on Oct. 28. The $229 million project will consolidate all UTHealth Houston School of Public Health operations into one facility. It will also connect students who are at the Austin, Brownsville, Dallas, El Paso and San Antonio campuses with peers and faculty through digital and distance learning.

Disciplines taught in the new tower will include epidemiology, genetics, nutrition, health policy, data science and health promotion, UTHealth shared when the building first broke ground in 2023.

Architects Kirksey Architecture and Smith Group designed the building, and Vaughn Construction served as general contractor. The facility features labs for studying human disease, classrooms and spaces to support interdisciplinary and community-based research, a broadcast studio and a teaching kitchen. A skybridge over Old Spanish Trail connects the new tower with a plaza that's shared with MD Anderson.

“This new facility reflects the kind of forward-looking investment that will serve Texans for generations,” Janiece Longoria, vice chairman of the UT System Board of Regents, said in a news release. “By creating an environment where talented people can learn, collaborate, and pursue new ideas, UTHealth Houston is building capacity to meet the challenges of tomorrow while strengthening its impact across our state.”

UTHealth says the system aims for the new campus to expand on collaborative research efforts and continue graduate education, as enrollment at the School of Public Health has increased by 27 percent over the last five years.

“This new building, with its state-of-the-art education technology and learning environment, will strengthen and advance the school’s mission to educate and train the next generation of experts who will advance scientific discovery, shape evidence-based health policy, and lead innovative solutions to the complex health challenges in communities throughout Texas and across the nation,” Kevin Morano, senior vice president, provost and chief academic officer of UTHealth Houston, added in a news release.

Attending the ceremony were Dr. Melina R. Kibbe, UTHealth Houston president and Alkek Williams Distinguished Chair; Eric Boerwinkle, dean, M. David Low Chair in Public Health and Kozmetsky Family Chair in Human Genetics at the School of Public Health; Texas State Representative Lauren Ashley Simmons, Texas House District 146; representatives of the offices of Senator John Cornyn and Harris County Commissioner Rodney Ellis; and Dr. Theresa Tran, director of the Houston Health Department.

"This building represents far more than a home for our school,” Boerwinkle added in the release. “It represents the people who make our mission possible: the faculty, staff, and students who fill each laboratory and classroom with curiosity, discovery, and purpose to improve the population’s quality of life.”

Rice University breaks ground on new innovation hub, The Arc

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Construction is officially underway on Rice University's The Arc in Houston’s Ion District.

The university broke ground on the 200,000-square-foot research, corporate innovation and office building on Nov. 4. The facility will share a plaza with the existing Ion building, fostering collaboration within the innovation space, according to Rice.

“The Arc will bring Rice’s extraordinary research and talent and Houston’s impactful innovation ecosystem into even closer connection with the industries and innovators working to solve some of the world’s most consequential challenges,” Rice President Reginald DesRoches said in an announcement. “That constant exchange of ideas and expertise will help move discoveries more rapidly from the laboratory to real-world impact.”

Construction is scheduled to be completed by Q2 2028. Rice Real Estate Co. is developing the project, and Rice University will occupy about 80,000 square feet in the building (about 40 percent). Preleasing has begun, with floor plans ranging from 28,000 to 31,000 square feet.

The Arc will feature conference and meeting spaces, an amenity lounge, fitness center, outdoor plazas, underground parking, and on-site retail and dining, according to the release.

It aims to host tenants focused on artificial intelligence and machine learning, data science, robotics, quantum science and engineering and energy, including Rice's new AI Foundry.

Rice says the AI Foundry will be a space where university experts and partners can support organizations with AI challenges. Rice recently committed to hiring 75 new AI-focused faculty and announced plans to launch a new Master of Artificial Intelligence (MAI) next fall.

“The AI Foundry is exactly the kind of collaboration the Arc is designed to enable,” Amy Dittmar, the Howard R. Hughes Provost and executive vice president for academic affairs at Rice, added in the release. “By bringing Rice researchers together with industry partners in a shared environment, we can accelerate the movement of ideas from research into practical applications while helping organizations build the capabilities they need to succeed as AI continues to evolve.

Developers of The Arc are targeting LEED Gold certification by incorporating smart building automation and energy-saving features into the project's design. Rice first announced the project in September 2025.

Rendering courtesy Bogza

Houston battery tech startup FlowCellutions acquired by Katy energy co.

M&A

Katy-based TerraFlow Energy, an energy storage and infrastructure company, has acquired Houston-based battery technology startup FlowCellutions. Financial terms weren’t disclosed.

FlowCellutions still operates under its established name, but with the tagline “A TerraFlow Energy Company.” Becca Segel, founder and CEO of FlowCellutions, now runs the business as its president.

FlowCellutions specializes in electrochemical sensing, diagnostics, analytics, and testing that offer insights into battery chemistry, charging capabilities, and system performance.

“FlowCellutions has always been focused on developing better ways to understand what is happening inside a flow battery and using that information to improve how these systems perform,” Segal said in a press release. “Joining TerraFlow gives us the opportunity to apply that work at a much larger scale while continuing to build the capabilities and expertise that make FlowCellutions unique.”

The FlowCellutions platform supports data centers and other heavy users of power. It’s designed to help reduce operating costs, prevent failures and costly downtime, and extend battery lifetime from about seven years to more than 30 years.

Segel founded the company in 2022. A member of Greentown Labs, the company raised more than $2 million in non-dilutive funding and received $1.5 million in National Science Foundation funding earlier this year.

FlowCellutions is one of five finalists in the Energy Transition Business category of InnovationMap’s 2026 Houston Innovation Awards.

“FlowCellutions brings a depth of scientific and technical expertise that fits naturally with where TerraFlow is going,” Jon Parrella, CEO of TerraFlow, said in the release.

“As we move from developing these systems to deploying them at commercial scale, understanding performance at a deeper level matters,” he said. “Bringing FlowCellutions into TerraFlow strengthens that capability and gives both teams more opportunity to advance the technology.”TerraFlow, founded in 2024, develops long-duration energy storage and power infrastructure for data centers, industrial facilities, utilities and other large power consumers.

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This article originally appeared on EnergyCapitalHTX.com.