MFN wake-up call: platforms and energy under antitrust scrutiny

Price parity clauses (also known as most favoured nation (MFN) clauses or best price clauses) have become one of the highest-priority enforcement targets in European competition law. These clauses, which require suppliers to offer a platform terms at least as favourable as those available through any other sales channel, can restrict price competition, raise barriers to entry for rival platforms, and ultimately harm consumers. The regulatory framework has evolved significantly in recent years. The revised EU Vertical Block Exemption Regulation (VBER) excludes wide MFN clauses from block exemption, requiring individual competition law assessment (see our March 2026 update), while the Digital Markets Act (DMA) explicitly prohibits MFN clauses by designated gatekeepers. Digital platforms, marketplaces, and comparison services across all sectors are affected: the use of parity mechanisms is subject to intensifying regulatory scrutiny.

National competition authorities have also continued to take enforcement action: most recently, the German Federal Cartel Office (FCO) secured commitments from Check24 (Germany's leading energy comparison platform) requiring it to abandon all price parity clauses in its contracts with energy suppliers.

What you need to know

• Check24, which holds a significant share of online energy contract brokerage in Germany, has committed to stop using price parity clauses that restrict energy suppliers from offering lower prices elsewhere. Check24 is no longer allowed to make commission levels or contractual terms dependent on suppliers' pricing behaviour on other sales channels, or to reduce supplier visibility or ranking based on prices offered elsewhere (a practice referred to as "dimming").
• The FCO emphasised that while comparison portals are generally pro-competitive, competition between portals must not be distorted by parity clauses that soften price competition and raise barriers to entry for alternative platforms.
• The decision aligns with the evolving EU regulatory framework: the revised VBER excludes wide MFN clauses and requires individual assessment under Article 101 of the Treaty on the Functioning of the European Union (TFEU). The DMA explicitly prohibits MFN clauses by designated gatekeepers.
• Any business that uses or is subject to parity mechanisms – whether as a platform operator, a supplier, or an intermediary – should review its contractual arrangements, as regulators are increasingly likely to intervene across all sectors and business models.

MFN clauses: a primer

In the context of conventional commercial agreements in the platform economy, MFN or parity clauses are contractual provisions that require a supplier to offer a platform terms (typically prices) that are at least as favourable as those offered through any other sales channel. In practice, this usually means a seller agreeing to offer its product or service to the buyer at a price no higher than the price it sets with another competing buyer. In the platform economy, online intermediaries such as hotel booking platforms, price comparison websites, and e-commerce marketplaces have often used these clauses.

Competition authorities and practitioners commonly distinguish between wide MFN clauses and narrow MFN clauses:

• Wide MFN clauses require the supplier to offer the platform the best price compared to all other channels, including competing platforms and the supplier's own direct sales. This prevents suppliers from offering better prices anywhere else and can significantly restrict competition between platforms.
• Narrow MFN clauses require the supplier to offer the platform the best price compared only to the supplier's own direct sales channels. This permits suppliers to offer better prices on competing platforms, but not via their own websites or other direct channels.

Platforms have historically justified MFN clauses as necessary to prevent free-riding where consumers use the platform to search and compare products but then complete transactions elsewhere (often directly with the supplier) at a lower price. Platforms have argued that, without the protection offered by MFN clauses, their business model is unsustainable because they bear the cost of customer acquisition without capturing the transaction. MFN clauses can also create pro-competitive benefits through reduced prices for end consumers.

However, competition authorities and courts across the EU have increasingly found that MFN clauses raise significant competition concerns, including:

• Collusion: MFN clauses can encourage competitors to align their prices (through both tacit and explicit collusion), because they reduce incentives to offer discounts and make it easier to notice when someone undercuts the agreed price, especially when many market participants use similar clauses.
• Softening of price competition: MFN clauses reduce suppliers' incentives to compete on price across different channels, as any price reduction must be extended to the MFN-protected platform.
• Higher intermediary fees: when suppliers cannot compete on price, platforms face less competitive pressure to lower their commission rates and costs are ultimately passed on to consumers.
• Barriers to entry: new or smaller platforms cannot attract suppliers by offering lower commissions in exchange for lower consumer prices, because suppliers are contractually prevented from passing on those savings.

The Check24 decision: FCO clamps down on price parity

Background to the Proceedings

In July 2025, the German FCO opened proceedings against Check24, Germany's leading online price comparison platform. Check24 operates across multiple sectors, including energy, insurance, and telecommunications and holds a strong position in the German energy comparison market. According to market studies referenced by the FCO, approximately 57% of new gas and electricity supply contracts in Germany are concluded via online intermediary services, with Check24 capturing an estimated 60 to 70% of those transactions.

The FCO's investigation examined Check24's use of parity obligations in its contracts with energy suppliers. These provisions (commonly referred to as price parity clauses, MFN clauses, or best price clauses) required energy suppliers to offer Check24 prices at least as favourable as those available through any other channel, including competing comparison websites, the suppliers' own websites, call centres, and offline sales channels. The effect of these clauses was to prevent suppliers from offering lower gas and electricity prices anywhere other than on Check24.

The FCO's competition concerns

The FCO identified competition concerns arising from Check24's use of parity clauses. A platform with Check24's market share restricting suppliers from offering better prices through alternative channels can distort competition both between comparison portals and between online platforms and other distribution routes. As the FCO highlighted in its press release, such clauses enable a platform to raise commissions or reduce service quality without meaningful competitive pressure because suppliers bound by them cannot offer more favourable prices on rival platforms or through their own channels.

Check24's commitments

To resolve the proceedings without a formal prohibition decision, Check24 offered commitments which the FCO accepted. The commitments require Check24 to:

• stop relying on existing parity clauses: Check24 will not enforce parity clauses relating to the brokerage of energy supply contracts;
• remove all parity clauses from existing contracts by no later than 31 December 2026;
• refrain from including parity clauses in any future contracts relating to the brokerage of energy supply contracts; and
• ensure that neither brokerage commission levels nor the ranking or visibility of tariffs on Check24 depend on the prices energy suppliers charge through other channels. This includes a ban on "dimming": a practice of reducing a supplier's visibility or ranking solely for lacking price parity. Ranking is to depend on factors such as the tariff price on Check24, its relative attractiveness, customer ratings, and customer behaviour on the platform but expressly not on the supplier's pricing elsewhere.

The commitments apply across all distribution channels, including suppliers' own direct channels such as websites and call centres. The FCO confirmed that it will not initiate administrative fine proceedings in relation to the conduct covered by the commitment decision. A commitment decision does not constitute a final determination that Check24 infringed competition law; rather, the decision reflects the FCO's acceptance of remedies addressing its competition concerns without the need for a formal finding of infringement.

The EU's tightening grip: regulatory framework

The Check24 decision reflects a broader enforcement trend against MFN clauses across Europe. Competition authorities and courts in Germany, the UK, France, Italy, Sweden, and at EU level, have increasingly intervened against parity obligations, particularly in the online travel, hotel booking, insurance comparison, e-commerce, and digital platform sectors. Several landmark rulings have confirmed that both wide and narrow MFN clauses can restrict competition by softening price rivalry, raising commission levels, and limiting merchants' ability to use alternative channels. Competition authorities have also been sceptical of free-riding arguments, consistently finding them insufficient to justify the competitive harm caused by MFN clauses. Companies operating digital platforms, marketplaces, and comparison tools should therefore be aware that MFN provisions remain a high-priority area of scrutiny in the evolving regulatory landscape.

The revised VBER

At the EU level, the approach to parity or MFN clauses has tightened significantly in recent years. The revised VBER removes block exemption protection for wide cross-platform retail parity obligations imposed by online intermediation services. These wide MFNs (which prevent business users from offering better prices or conditions on competing platforms or their own websites) are now listed as excluded restrictions requiring individual assessment under Article 101 TFEU. Other types of parity obligations, including narrow retail MFNs and wholesale MFNs, may still benefit from the block exemption where the VBER conditions (notably the 30% market-share threshold) are met. Where a clause benefits from the block exemption, it is presumed to satisfy Article 101(3) TFEU without the parties needing to demonstrate efficiencies, consumer benefits, indispensability, or the absence of foreclosure effects. However, the European Commission may withdraw the exemption where narrow MFNs used by large platforms generate significant cumulative effects not outweighed by demonstrable efficiencies.

The DMA

For designated gatekeepers, the DMA introduces an explicit prohibition on MFN clauses. Under Article 5(3) of the DMA, gatekeepers are prohibited from requiring business users to offer goods or services on the gatekeeper's platform at prices or conditions equal to or more favourable than those offered on third-party platforms or through business users' own direct sales channels (so-called wide MFN or parity clauses).

While the DMA's MFN prohibition applies directly only to designated gatekeepers (such as operators of large app stores, online social networking services, and online intermediation and e-commerce platforms), its scope should not be read as defining the outer boundary of regulatory concern. Rather, the prohibition signals a clear regulatory trend towards stricter treatment of MFN clauses across the digital economy. Platforms that do not meet the gatekeeper designation thresholds should not assume that their MFN practices will escape regulatory or enforcement scrutiny. As the Check24 case demonstrates, national competition authorities remain willing and active in enforcing general competition law against parity clauses imposed by non-gatekeeper platforms. The DMA's underlying policy rationale (that MFN clauses distort competition and ultimately harm consumers) is equally applicable to non-gatekeeper platforms that hold significant market positions.

Outlook: platform power meets energy policy

The Check24 decision underscores the intensifying scrutiny of MFN clauses across the digital economy and highlights why competitive dynamics on intermediary platforms matter particularly in sectors of vital importance to consumers, such as energy.

The energy sector illustrates the practical significance of this enforcement trend. Consumers depend on comparison platforms to navigate complex and often volatile energy markets, making the competitive functioning of those platforms directly relevant to consumer welfare. In its February 2026 Market Power Report on the competitive landscape in the generation of electricity, the FCO underlines this concern: major energy generators hold significant structural market power, given their pivotal role in meeting electricity demand during critical hours. Where intermediary platforms further constrain price competition through MFN clauses, the cumulative effect on consumer choice and pricing can be substantial.

Consumer switching remains one of the most effective mechanisms for disciplining retail energy prices. In their joint Monitoring Report 2025, published in November 2025, the FCO and the Federal Network Agency (Bundesnetzagentur) recorded record-high switching levels in 2024, with a 14% switching rate for electricity customers and a 17.7% switching rate for gas customers. These switching rates arguably underline the important role of intermediary platforms in helping consumers navigate the market and secure competitive tariffs. As FCO President Andreas Mundt puts it: "[c]omparison websites make it easier for consumers to switch suppliers, which has a generally pro-competitive effect. However, it is important that there is also effective competition between comparison websites and other sales channels".

The Check24 decision also forms part of a broader regulatory stance toward digital platforms. In FCO President Mundt's words, "[w]hen a company attempts to influence the pricing of its contractual partners, this routinely raises competition law concerns – especially if that company is a leading provider". This logic extends beyond the energy sector and beyond explicit contractual terms. Functional equivalents to price parity clauses, such as algorithmic "dimming" or ranking penalties, may well fall under regulatory scrutiny.

The compliance message is clear. Platform providers should reassess contractual parity obligations that penalise off-platform price differentiation. In practice, this means reviewing MFN clauses and auditing ranking, visibility, and commission rules to ensure that they do not restrict suppliers' freedom to compete on price across channels. The Check24 outcome signals that competition authorities will intervene where platform practices undermine effective competition – and that sectors where consumers are most reliant on intermediary platforms, such as energy, are likely to remain at the forefront of enforcement.

Other author: Dimitra Karakioulaki, Associate and Sarah Schaible, Transaction Lawyer