Why the CMA thinks a decades-old benchmarking platform could have been softening competition at Hilton, IHG Hotels and Marriott

The UK Competition and Markets Authority (CMA) has launched a formal investigation into three of the world’s largest hotel operators — Hilton Worldwide Holdings (NYSE: HLT), InterContinental Hotels Group (LSE: IHG, NYSE: IHG), and Marriott International (NASDAQ: MAR) — alongside CoStar Group (NASDAQ: CSGP), the commercial real estate data and analytics company that owns the hotel benchmarking tool STR. The CMA is probing whether the hotel chains used STR to share competitively sensitive information with one another, in a manner that may have softened competition and reduced pricing uncertainty among rivals. The investigation, announced on 2 March 2026, represents the most significant regulatory action in the UK against the hospitality sector’s use of shared data infrastructure and sits within a fast-accelerating global wave of scrutiny directed at algorithmic and data-sharing arrangements across consumer industries. Together, the three hotel groups operate more than 25,000 hotels globally, giving the probe significant weight in the international hospitality sector.

How does CoStar’s STR benchmarking tool work and why is the CMA concerned about it now?

STR, originally known as Smith Travel Research, has operated as the hospitality industry’s standard performance benchmarking service for decades. CoStar Group acquired STR in 2019, adding the platform to its commercial real estate data business alongside property databases, marketplace listing platforms, and analytics services across office, retail, and multifamily segments.

Hotel chains routinely use analytics platforms such as STR to track industry metrics including occupancy rates, average daily room prices, and revenue per available room, known as RevPAR. The mechanism at the centre of the CMA’s concern is the data exchange structure built into the platform: a hotel operator must contribute its own data to STR in order to receive benchmarking information in return, creating a reciprocal data flow between competing chains using the same third-party intermediary. Operators also know exactly which competitors are participating in the exchange and how often, because to receive STR’s reports, a participating operator must first select a competitive set.

The CMA has been explicit about its theory of harm: when rival businesses share commercially sensitive data through a common intermediary, competitive uncertainty diminishes. If hotels can observe one another’s occupancy trajectory, daily rate trends, and RevPAR performance in near-real time, the analytical gap that would normally drive independent pricing decisions narrows materially. The watchdog does not need to prove that hotel executives sat in a room and agreed to raise prices. The concern is structural, not conspiratorial: the architecture of the data-sharing arrangement may itself function as a coordination mechanism.

What are the potential penalties and how has the industry responded to the investigation?

If the CMA concludes that competition rules have been breached, it has the power to impose fines of up to 10% of a company’s global annual turnover. For Marriott International, which reported approximately $26 billion in revenue for 2025, that theoretical ceiling runs into the billions. Hilton and InterContinental Hotels Group operate at comparable scale. CoStar’s exposure at that threshold would exceed $300 million based on its 2025 revenues of $3.25 billion.

InterContinental Hotels Group and Hilton both confirmed they were cooperating fully with the CMA’s investigation. CoStar stated it was surprised at the CMA’s interest in what it described as a long-standing hotel data analytics and benchmarking platform used for decades by companies and government entities alike. Marriott did not respond immediately to requests for comment. The CMA has made clear that no assumptions of wrongdoing should be made at this stage, and a formal statement of objections would only follow if the regulator provisionally determines that competition law has been infringed.

The CMA’s leniency policy remains open: any business involved in cartel activity can apply for immunity from penalties or a significant reduction in fines in exchange for reporting the conduct and cooperating with the investigation. That provision is not incidental. Its inclusion in the formal announcement sends a deliberate signal to the parties that first-mover advantage exists for any entity willing to come forward with substantive information.

How does the CMA investigation connect to the broader global crackdown on algorithmic pricing and data-sharing arrangements?

The CMA’s probe does not emerge in isolation. It comes amid rising global concern about how algorithms, pricing software, and shared datasets may affect market competition, particularly in sectors such as travel, housing, and retail where dynamic pricing is widespread.

In the United States, the Federal Trade Commission and the Department of Justice’s Antitrust Division have both moved aggressively on related fronts. The FTC and DOJ filed a joint statement of interest making clear that hotels cannot collude on room pricing and cannot use an algorithm to engage in practices that would be illegal if done by a real person, and that competitors cannot lawfully cooperate to set prices, whether via their staff or an algorithm, even without direct communication between them.

The RealPage case in the US multifamily housing sector has become the defining precedent for this theory. Two algorithm vendors serving that market — RealPage and Yardi Systems — face similar class-action antitrust lawsuits, and 27 property firms agreed to pay a combined $141 million to settle one class action, while RealPage also faces a civil antitrust suit filed by the DOJ and attorneys general in eight states.

The hotel sector specifically had a partial reprieve in the US. CoStar and a group of hotel companies won dismissal from a putative antitrust class action when a Washington federal judge drew a distinction between the use of hotel industry benchmarking data and algorithmic rental pricing software. In November 2025, the Ninth Circuit denied rehearing, leaving in place the August 2025 panel decision affirming that dismissal. The CMA is not bound by US jurisprudence, however, and UK competition law operates on its own procedural and evidentiary framework under the Competition Act 1998.

What does the investigation mean for CoStar Group’s business model and its stock, which is trading near a 52-week low?

For CoStar Group, the CMA investigation arrives at a particularly uncomfortable moment. As of late February 2026, CSGP shares were trading at approximately $44.63, against a 52-week high of $97.43 and a 52-week low of $43.17, meaning the stock had shed roughly half its value over the prior twelve months. The company is already contending with institutional pressure from Daniel Loeb’s Third Point over capital allocation discipline, weaker-than-expected Q1 2026 guidance that sent shares down sharply after its Q4 results, and a BTIG analyst price target reduction to $60 from $80 in late February.

Against that backdrop, a formal regulatory investigation from the UK’s primary competition authority into CoStar’s most historically established data product introduces a material new risk dimension. STR is not a peripheral offering. It is the benchmarking infrastructure that underpins the hospitality vertical of CoStar’s international data business, used by major hotel chains and government bodies worldwide. A finding of infringement would not merely expose CoStar to financial penalties. It could require structural changes to how STR collects, aggregates, and distributes data, threatening the commercial logic of the platform and the network effect that makes it valuable.

Morningstar analysts have flagged that emerging threats including AI and data-sharing arrangements could have the potential to disrupt CoStar’s core business model. The CMA investigation gives that concern a specific regulatory shape.

How will Hilton, InterContinental Hotels Group, and Marriott International navigate the reputational and operational fallout?

For the hotel operators, the investigation poses a different set of strategic considerations than it does for CoStar. None of the three chains are accused of building or selling the tool. Their exposure relates to their use of it and what data they contributed. That distinction matters in terms of potential liability, but it does not fully insulate them from reputational risk, particularly in a consumer market where room pricing transparency is already a contentious issue.

InterContinental Hotels Group shares fell as much as 5% in early trading following the announcement, the most immediate market signal of investor concern among the hotel operators, reflecting its UK listing and the direct jurisdiction of the CMA. The ADR traded at approximately $131.80 as of 2 March 2026, down from $139.85 at the prior close, and sits within a 52-week range of roughly $94.78 to $150.89. Hilton Worldwide Holdings, which had reached an all-time high of $333.86 on 12 February 2026, was also under scrutiny in early trading, though the stock has been broadly supported by strong Q4 results. Marriott International, trading at approximately $358.75 ahead of the announcement, faces similar investor attention.

All three chains derive substantial income from management and franchise fee structures rather than direct room ownership, which limits their direct balance sheet exposure to any specific pricing outcome. The more consequential risk is that a CMA finding of infringement could require renegotiation of data-sharing practices globally, disrupt revenue management workflows built around STR data for years, and invite parallel investigations in other jurisdictions.

The European Commission has been active on algorithmic coordination questions, and competition authorities in Australia, Canada, and several US states have expanded their enforcement capacity in recent years. The CMA investigation may function as a legal catalyst that prompts parallel reviews elsewhere, particularly in jurisdictions where the hotel sector’s benchmarking practices have not yet been formally examined.

Key takeaways on what the CMA’s hotel data investigation means for CoStar, Hilton, IHG Hotels, Marriott, and the hospitality industry

• The CMA has opened a formal investigation under the Competition Act 1998 into whether Hilton Worldwide Holdings, InterContinental Hotels Group, and Marriott International used CoStar’s STR benchmarking tool to share competitively sensitive information that may have reduced pricing competition.
• CoStar Group (CSGP) faces the most concentrated business risk from the probe, as STR is a core component of its hospitality data business and the investigation threatens both the commercial model and the legal defensibility of the platform’s data exchange structure.
• CSGP shares were already trading near a 52-week low of approximately $43.17 ahead of the announcement, down roughly 55% from their 52-week high, compounding existing investor concerns about capital allocation, weak forward guidance, and institutional pressure from activist shareholders.
• InterContinental Hotels Group shares fell as much as 5% on the day of the announcement, the most immediate market signal of investor concern among the hotel operators, reflecting its UK listing and the direct jurisdiction of the CMA.
• The CMA’s maximum penalty is 10% of global annual turnover, representing billions in theoretical exposure across all four companies, though formal penalties would only follow a full investigation and provisional finding of infringement.
• The investigation is structurally connected to a global enforcement wave targeting algorithmic and data-intermediated coordination, including the RealPage multifamily housing litigation in the US, FTC and DOJ statements on hotel pricing algorithms, and legislative activity across multiple jurisdictions.
• US courts dismissed a similar class-action against CoStar and hotel operators in September 2025, distinguishing benchmarking data from algorithmic pricing software. The CMA operates under separate UK law and is not bound by that precedent.
• The leniency policy open to participating companies introduces an incentive for early cooperation that may accelerate the CMA’s information-gathering and complicate the collective litigation strategy of the respondents.
• Hospitality revenue management systems built around STR data could require significant redesign if the investigation results in restrictions on the nature of data that can be shared through third-party intermediaries.
• The broader implication for data analytics businesses across sectors is clear: providing a shared data infrastructure to competing firms in the same market now carries explicit regulatory risk, regardless of whether the vendor itself sets or recommends prices.