Fifth Third–Brex Deal Puts $5.6B AI-Powered Card Platform at Center of Comerica Merger Fight

As Fifth Third Bank chooses Brex to power its commercial cards, the regional lender faces activist lawsuits and community protests over its planned Comerica acquisition.

CINCINNATI / DALLAS / NEW YORK — December 10, 2025

Key Points

Fifth Third Bank has signed a multi‑year partnership with fintech Brex that will make Brex the default technology platform behind its commercial card offering, covering roughly $5.6 billion in annual card payment volume. ^[1]
The “Fifth Third Commercial Card powered by Brex” will let commercial clients issue corporate cards, automate expense management and use AI agents to control spend and close the books faster. ^[2]
The move lands just as Fifth Third pushes ahead with its $10.9 billion all‑stock acquisition of Comerica, a deal slated to create the ninth‑largest U.S. bank with around $288 billion in assets, pending approvals. ^[3]
Activist investor HoldCo Asset Management has sued Comerica and Fifth Third, alleging the merger was “rushed” and overly protective of management, while community groups are challenging the deal on fair‑lending and branch‑closing grounds. ^[4]
As of December 10, 2025, analysts and industry watchers see the Brex tie‑up as a template for mid‑tier banks that want AI‑driven payments and expense tools without spending years building in‑house platforms. ^[5]

Fifth Third turns to Brex for AI‑powered commercial cards

On December 9, Fifth Third Bank announced a multi‑year partnership with Brex, under which the fintech will power the bank’s commercial card program across its commercial banking franchise. ^[6]

According to the joint announcement, the deal:

Unlocks about $5.6 billion a year in commercial card payment volume, which will now run on Brex Embedded, the company’s API‑driven payments infrastructure. ^[7]
Makes the Fifth Third Commercial Card powered by Brex the default commercial card solution for Fifth Third’s commercial banking clients. ^[8]
Gives those clients access to Brex’s “intelligent finance” software — including card issuing, automated expense management, real‑time payments and workflow automation. ^[9]

Fifth Third CEO and chair Tim Spence framed the move as a strategic bet on AI‑native infrastructure. In the press release, he said “the future of business demands financial platforms that do more than process payments—they must power growth.” ^[10]

Brex CEO Pedro Franceschi, meanwhile, highlighted the bank’s scale, noting that Fifth Third touches roughly 8% of the U.S. commercial banking sector, giving Brex a single partner route into a huge swath of business customers. ^[11]

What the new card platform actually does

Between the company statements and trade‑press coverage, the partnership centers on three pillars: ^[12]

AI‑driven expense management
- Automated classification of transactions and receipts
- Policy checks to flag out‑of‑policy spend
- Real‑time budget and spend analytics for finance teams
Embedded payments infrastructure
- Card issuing and controls via Brex Embedded APIs
- Real‑time payments and international transaction support
- Direct integrations with accounting and ERP systems
“Agentic” finance workflows
- AI agents that can route approvals, chase missing receipts, and help finance teams close the books faster
- Less manual review and data entry, more exception‑based oversight

PYMNTS, which also reported on the deal on December 9, stresses that Fifth Third’s commercial card clients will gain exactly this combination of card issuing, AI‑assisted expense tools and real‑time payments, all within a single platform. ^[13]

The partnership also builds on Brex’s Brex Embedded product, launched in 2024, which lets banks and software platforms plug in Brex’s global card and payments capabilities via APIs instead of building their own stack. ^[14]

Why Fifth Third is partnering instead of building

Coverage from CNBC and technology outlets underscores a bigger story: mid‑tier banks are increasingly licensing fintech platforms instead of trying to replicate them from scratch. ^[15]

CNBC’s report — amplified on LinkedIn and X because the article itself is behind stricter web access — notes that:

The program will run on Brex’s embedded payments platform.
Banks like Fifth Third are choosing to partner with fintechs to keep pace with clients’ technology expectations.
All of this is happening while Fifth Third is in the process of acquiring Comerica. ^[16]

TechBuzz, which updated its analysis on December 10, characterizes the deal as a “pivotal shift” in strategy: rather than spend years and hundreds of millions customizing legacy systems, Fifth Third effectively outsources a chunk of its commercial card technology to a fintech that already serves startups and large enterprises. ^[17]

There’s a hard‑nosed business logic here:

Time‑to‑market: Plugging into Brex’s platform gives Fifth Third modern card controls, AI expense tools and global capabilities now, not in 3–5 years. ^[18]
Capital allocation: Instead of building duplicative infrastructure, Fifth Third can focus capital on acquisitions (like Comerica), new branches and other growth initiatives. ^[19]
Competitive table stakes: CFOs now expect real‑time visibility, automation and AI‑driven anomaly detection; legacy spreadsheet‑heavy card programs are increasingly a liability. ^[20]

For Brex, the partnership is a validation of its “intelligent finance” and embedded‑banking strategy, as it moves beyond startups into the balance sheets of large regional banks. ^[21]

Comerica acquisition: the big deal in the background

All of this lands against the backdrop of a high‑stakes bank merger.

On October 6, 2025, Fifth Third and Comerica announced a definitive agreement under which Fifth Third will acquire Comerica in an all‑stock transaction valued at $10.9 billion. ^[22]

Key terms and implications from the banks’ own disclosures:

Comerica shareholders will receive 1.8663 Fifth Third shares for each Comerica share, implying about $82.88 per share at announcement. ^[23]
The combined bank is expected to become the 9th‑largest U.S. bank, with roughly $288 billion in assets and a footprint spanning high‑growth markets across the Southeast, Texas, Arizona and California, in addition to the Midwest. ^[24]
Management is targeting closing by the end of Q1 2026, subject to shareholder and regulatory approvals. ^[25]

The merger is pitched as a way to:

Add Comerica’s strong middle‑market franchise to Fifth Third’s existing strengths in retail, payments and digital,
Create two $1‑billion‑plus recurring fee businesses (Commercial Payments and Wealth & Asset Management), and
Deepen density in growth markets while retaining Midwest scale. ^[26]

From that perspective, handing the commercial card stack to Brex looks like pre‑merger plumbing: get a scalable, AI‑driven spend platform in place now, then roll it out across the enlarged customer base if and when the Comerica deal closes.

Legal and community blowback intensifies

But the path to that larger bank is anything but smooth as of December 10.

Activist investor lawsuit in Delaware

On November 25, activist investor HoldCo Asset Management filed a class‑action complaint in the Delaware Court of Chancery against Comerica, its board and Fifth Third. ^[27]

According to Banking Dive’s summary of the filing, HoldCo alleges that: ^[28]

Comerica’s board breached its fiduciary duties by agreeing to what the investor calls a “draconian” merger agreement, including a $500 million termination fee and a very narrow “fiduciary‑out” clause.
The deal was negotiated over just 17 days, making it unusually fast compared with other large bank mergers, and allegedly driven in part by CEO Curt Farmer’s desire to secure a lucrative role at the combined company.
Comerica’s disclosures lacked key details, including comparisons with at least one other suitor (“Financial Institution A”), believed to be Regions Bank.

Fifth Third is accused of aiding and abetting those alleged breaches, a claim the bank’s lawyers call meritless in court filings. ^[29]

A shareholder vote on the merger is tentatively set for January 6, 2026, with Delaware proceedings moving on an expedited timeline. ^[30]

CRA and fair‑lending protests

At the same time, community and fair‑lending groups are targeting the deal from another angle: the Community Reinvestment Act (CRA) and mortgage‑lending patterns.

Reporting from Inner City Press and its advocacy arm, Fair Finance Watch, describes a multi‑front campaign: ^[31]

Fifth Third announced its intent to buy Comerica in October, then filed its application with the Federal Reserve on December 1.
The bank is allegedly seeking to withhold details of planned branch closures in its regulatory filings, prompting FOIA challenges arguing that the public needs to see which communities may lose local branches.
Fair Finance Watch points to 2024 Home Mortgage Disclosure Act (HMDA) data, claiming that in states like Michigan and Florida, Fifth Third denied more mortgage applications from Black borrowers than it originated, while approving many more loans for white borrowers.

The group argues that this pattern, if accurate, should weigh heavily in CRA and fair‑lending reviews of the Fifth Third–Comerica merger and related branch applications. ^[32]

So while Fifth Third is promoting its Brex partnership as part of a push toward more efficient, AI‑powered finance, it is simultaneously being challenged on whether its growth strategy could deepen disparities in credit and branch access.

How the Brex deal and Comerica merger intersect

Even though they’re technically separate transactions, the Brex partnership and Comerica merger are deeply connected in how investors and regulators now view Fifth Third.

Scale demands modern infrastructure

If the merger closes, Fifth Third will inherit Comerica’s sizable commercial and middle‑market client base, especially in Texas, California, Arizona and Florida. ^[33]

Those clients increasingly expect:

Real‑time card controls and virtual cards for distributed teams
Automated expense and invoice workflows
Seamless integration into ERP and accounting systems

By making Brex its default commercial card platform before the merger closes, Fifth Third is effectively saying:

“We’ll standardize on a cloud‑native, AI‑driven system now, then unify both banks’ clients on that stack later.”

That could simplify integration and provide a consistent customer experience across the combined footprint.

Regulatory optics: tech upgrade vs. conduct concerns

On the other hand, loading more of the combined bank’s spend and transaction data into sophisticated AI systems raises its own regulatory questions:

Model governance & bias: If Brex’s AI agents are used to automate decisions around spend controls, risk scores, or even credit limits, regulators will want to know how those models behave across different customer segments. ^[34]
Data privacy & third‑party risk: Shifting a core product like commercial cards to a fintech partner puts more pressure on vendor‑risk frameworks, incident response planning and third‑party oversight. ^[35]
CRA narrative: Fifth Third will likely argue that modern data and analytics can help improve fairness and monitoring. Critics counter that tech upgrades are meaningless if branch closings and legacy lending disparities aren’t addressed. ^[36]

In short, the Brex deal strengthens Fifth Third’s technology story precisely while activists are attacking its conduct and governance story.

What this means for business customers

For Fifth Third’s and, potentially, Comerica’s commercial customers, the immediate practical impacts of the Brex partnership are likely to show up in four areas: ^[37]

Richer card controls and policy automation
- Configurable spending limits by team, project or vendor
- Automated enforcement of travel and expense policies
- Fine‑grained controls for virtual and one‑time cards
Less manual expense work
- Automated receipt matching and categorization
- AI‑assisted anomaly detection (duplicate receipts, out‑of‑policy spend)
- Faster month‑end close with fewer spreadsheets
Global‑ready operations
- Multi‑currency card support, depending on how Fifth Third rolls out Brex’s capabilities
- Better visibility into cross‑border spend for mid‑market companies expanding abroad
A single interface over time
- If regulators approve the Comerica merger, customers from both banks may eventually land on the same Brex‑powered spend platform, simplifying multi‑entity and multi‑region reporting.

Of course, timing and rollout details remain to be announced, and some large clients may have bespoke or legacy arrangements that take longer to migrate.

Risks and open questions as of December 10, 2025

Despite the upbeat messaging, several uncertainties could shape how this story looks a year from now:

Regulatory approvals for the merger
- The Federal Reserve, OCC and other regulators will weigh the CRA criticism, HMDA data and branch plans alongside the business case for the deal. ^[38]
- Activist litigation in Delaware could delay the shareholder vote or lead to new disclosures or revised terms. ^[39]
Execution risk on technology integration
- Even with a sophisticated partner, migrating tens of thousands of commercial cardholders to a new platform is a multi‑year project that must be staged carefully. ^[40]
Customer reception
- Many CFOs will welcome automation; others may worry about over‑automation or the learning curve of a new interface and workflows. ^[41]
Perception of priorities
- Community advocates may seize on the Brex deal as proof that the bank is ready to invest in AI and developer‑friendly platforms while allegedly trying to keep branch‑closure details out of public view. ^[42]

How Fifth Third balances those optics — highlighting “intelligent finance” on earnings calls while convincing regulators and communities that growth won’t worsen inequities — will matter as much as the underlying tech.

What to watch next

Looking beyond December 10, 2025, here are the key milestones and storylines to monitor:

January 6, 2026 (tentative): Shareholder vote on the Comerica acquisition, assuming the Delaware court doesn’t change the timetable. ^[43]
Regulatory decisions: Fed and OCC determinations on the merger and branch applications, including any conditions around fair‑lending and branch closures. ^[44]
Brex rollout details: Timeline for when new and existing commercial clients will be migrated to the Fifth Third Commercial Card powered by Brex, and which advanced AI features will be enabled first. ^[45]
Competitive response: Whether other regional banks announce similar large‑scale partnerships with spend‑management and embedded‑payments platforms over the coming quarters. ^[46]

Quick FAQ

Is the Fifth Third–Brex partnership already live?
The partnership has been announced and framed as a multi‑year deal; Fifth Third says the Brex‑powered commercial card will be the default solution for its commercial banking clients, but it has not yet published a detailed migration schedule. ^[47]

Does this change Comerica customers’ cards today?
Not yet. Comerica remains a separate bank until the merger closes, which is targeted for late Q1 2026 and still needs regulatory and shareholder approvals. Any extension of the Brex platform to Comerica clients would come later, if the deal is approved and integration plans move forward. ^[48]

Why not build this technology in‑house?
Industry coverage points out that regional banks like Fifth Third lack the scale of megabanks to justify years‑long, billion‑dollar internal builds. Partnering with a specialist platform like Brex lets them deliver AI‑powered card and expense tools faster while focusing internal resources on core banking, M&A and branch expansion. ^[49]

What are critics most worried about?
On the merger side, activists say the Comerica deal was rushed and too protective of management, and community groups are raising alarms about potential branch closures and lending disparities. On the tech side, regulators will be watching model risk, data governance and whether AI‑powered systems treat all customers fairly. ^[50]