Federal Court of Justice (BGH) on agent liability under the UWG: companies are liable for unfair competition violations of their advertising partners

Agent liability under the UWG is becoming increasingly significant in practice in connection with external service providers in online marketing. The current decision of the Federal Court of Justice (BGH) of 11.03.2026, Az. I ZR 28/25 makes clear that outsourcing does not result in a relief from liability. Companies can be held liable for unfair competition violations by third parties in accordance with § 8 Abs. 2 UWG.

Facts

The judgment was based on a competition law dispute between two companies that sold electrical appliances over the Internet. The defendant advertised its products via Google using standardized advertising formats, which were – at least in part – generated and played out by the platform itself.

In the context of these advertisements, products were advertised without the mandatory information on energy efficiency required under applicable EU law and national regulations being completely displayed. In particular, information on the energy efficiency class was missing, which is mandatory when advertising certain household appliances.

The specific design of the advertising was not undertaken directly by the defendant itself, but by Google. The defendant had concluded a cooperation agreement with Google, according to which it continuously transmitted certain information about products offered by it to Google, which Google placed for advertising information on its own websites or websites of the Google partner network. The defendant paid Google an agreed remuneration for each click on these advertising materials. The selection of channels, the scope and content of the advertisements were solely within the decision-making power of Google.

A competitor saw in this a violation of competition law provisions, in particular due to the withholding of essential information within the meaning of § 5a UWG, and demanded that the respondent cease and desist.

The respondent objected, asserting that it had no direct influence on the specific design of the advertising, since this had been implemented independently by Google.

Agent liability pursuant to § 8 Abs. 2 UWG – Decision of the BGH

With this decision, the BGH clarifies the requirements of agent liability pursuant to § 8 Abs. 2 UWG. According to this, companies are also liable for violations by persons who act as "agents".

According to the decision, an agency relationship is to be assumed when:

• the third party is integrated into the company's sales organisation and
• the activity objectively serves to promote sales.

It is irrelevant, however, whether the third party acts on its own responsibility in the individual case or whether there is complete control by the company.

In this respect, the BGH makes clear that liability is sufficient if the third party draws on information or structures provided by the company and acts in the context of sales promotion.

The appeal was therefore successful and led to the quashing of the decision appealed against and the remittal of the case to the Higher Regional Court (OLG) Bamberg.

Broad interpretation of the agency concept

The decision confirms the broad interpretation already evident in case law in the context of agent liability. Those covered by the term "agents" include in particular:

• advertising agencies
• operators of online platforms
• affiliate partners
• other external marketing service providers

This makes clear that even divided labour and digitalised marketing structures can fall completely within the sphere of liability responsibility of the company.

Practical implications

The decision makes clear that the engagement of external service providers does not fundamentally affect the competition law responsibility of the advertising company.

For practical purposes, this means above all that companies should keep track of the advertising measures they have arranged, regardless of whether these are implemented internally or by third parties. This applies in particular to those contents that are subject to statutory information requirements or are typically the subject of competition law objections.

In this context, it will generally be sufficient to ensure clear coordination with the engaged service providers and to communicate the essential legal requirements. In many cases, it would also be advisable to monitor advertising measures at least on a spot-check basis, in particular for standardised or automated campaigns.

The decision gives no cause to fundamentally question existing structures. However, it underscores that legal responsibility for the company's external representation cannot be completely transferred to third parties.

Conclusion

The decision of the Federal Court of Justice confirms the broad scope of agent liability pursuant to § 8 Abs. 2 UWG. Companies cannot successfully rely on the fact that unfair competition violations occurred as part of outsourced advertising measures.

Against this background, it is recommended to shape cooperation with external marketing service providers consciously from a legal perspective and to ensure compliance with central competition law requirements.

Do you have questions about the legally compliant design of your advertising measures or have you already received a cease-and-desist letter? We provide comprehensive advice on competition and trademark law – practical and solution-oriented.