VLOSE stands for very large online search engine, the heaviest supervisory tier of the European Union's Digital Services Act, Regulation (EU) 2022/2065. It attaches to search services recording at least 45 million average monthly active recipients inside the Union that the European Commission designates as such. The label is not self-applied. Designation converts a search engine into a supervised entity that must assess its own systemic risks, submit to annual audit, open data to vetted researchers, publish a searchable archive of every advertisement it carries in Europe and pay towards its own oversight. The category sits beside VLOP, very large online platform, and was kept separate because a search engine ranks material it does not host.

How a search engine becomes a VLOSE

Article 3(j) defines an online search engine as an intermediary service that allows users to input queries in order to search, in principle, all websites, on the basis of a keyword, voice request, phrase or other input, and that "returns results in any format". Nothing in that wording requires a list of blue links.

Every provider of an online platform or search engine, whatever its size, must publish its average monthly active recipients in the Union at least once every six months under Article 24(2). The first disclosures were due by 17 February 2023, and those self-reported figures are what the Commission works from.

Article 33(1) sets the trigger at 45 million, approximating 10% of the Union's population, and Article 33(2) obliges the Commission to adjust it by delegated act whenever that population moves at least 5% from its 2020 level. Under Article 33(3) the Commission may also define how the recipient count is calculated, a power it has not yet used.

Designation follows under Article 33(4), after consultation with the member state of establishment, and the service then has four months to comply. It can be withdrawn once a service stays below the threshold for a full year, as happened to the adult platform Stripchat on 27 May 2025.

What designation obliges

Section 5 of Chapter III, Articles 33 to 43, contains the asymmetric rules. Article 34 requires an annual assessment of systemic risks across four headings: illegal content, fundamental rights, civic discourse and electoral processes, and gender-based violence, public health, minors and mental wellbeing. Article 35 requires mitigation, expressly including changes to the design of the service and to its recommender systems. Article 36 creates a crisis response mechanism, Article 37 mandates an independent audit at least once a year, and Article 38 requires at least one recommender option not based on profiling.

Article 39 is the provision the advertising industry reads first. Designated platforms and search engines that carry advertising must compile a public repository in a specific section of the interface, reachable through a searchable tool supporting multicriteria queries and through an application programming interface. It must hold the creative content including the product, service or brand name and the subject matter; the entity on whose behalf the ad ran; the party that paid, where different; the period of presentation; whether it was targeted and on what main parameters; and the total recipients reached, broken down by member state where targeting applied. Entries stay up for the whole run and for one year after the last impression, and must carry no personal data.

Article 40 governs data access for vetted researchers, Article 41 requires an independent compliance function, and Article 42 sets transparency reporting at six-month intervals. Article 43 imposes the annual supervisory fee, capped at 0.05% of worldwide annual net income in the preceding financial year, with the mechanics in Delegated Regulation (EU) 2023/1127. Enforcement sits with the Commission rather than national regulators, and penalties reach 6% of worldwide annual turnover.

One asymmetry is easy to miss. Because a search engine is not an online platform under Article 3(i), the platform obligations in Articles 16 to 28 do not follow it. Article 26, which requires each advertisement to be identifiable in real time with the advertiser named and the main targeting parameters exposed, binds online platforms alone. Article 39 binds both. A designated search engine owes the archive without owing the per-impression disclosure.

Origin and evolution

The Commission proposed the Digital Services Act on 15 December 2020, the same day as the Digital Markets Act. Parliament and Council adopted it on 19 October 2022, publication followed on 27 October, and it entered into force on 16 November 2022. Article 92 pulled application forward for designated services.

The first designation decisions came on 25 April 2023, covering 17 very large online platforms and 2 very large online search engines. Google Search and Bing were the only search services on that list, and remained the only two for more than three years. The rest of the regulation applied to all intermediary services from 17 February 2024.

Why it matters for the marketing community

For anyone buying search inventory in Europe, Article 39 is the only statutory basis for a public archive of search advertising, and its disclosure duties run through the supply chain rather than stopping at the designated company. The IAB Tech Lab published a technical specification for DSA transparency in late 2023, scoped explicitly to VLOPs and VLOSEs, and IAB Europe reached version 1.2 of its carriage format, with templates in 24 languages, in December 2025.

The category now reaches conversational advertising too. OpenAI began serving sponsored placements to Free and Go users across 31 European markets in August 2026, weeks before its search function was designated. A VLOSE that sells advertising owes the Article 39 archive whether its results arrive as links or as generated prose.

There is a second-order effect on artificial intelligence governance. The consolidated AI Act text that took effect on 27 July 2026 gives the AI Office exclusive supervision of AI systems integrated into a designated platform or search engine.

Limitations and disputes

The recipient count the structure rests on has never been defined in binding law. On 10 September 2025 the General Court annulled the implementing decisions setting the 2023 supervisory fees for Facebook, Instagram and TikTok, in cases T-55/24 and T-58/24, holding that the method for calculating average monthly active recipients was an essential element of the fee and should have been adopted by delegated act. The Commission could rely on third-party estimates from SensorTower and Similarweb, according to the judgments, but not bury the method in individual decisions. Effects were maintained for up to 12 months, a window closing in September 2026. Google has a parallel challenge on file.

Designation itself has held up better. The same court upheld Zalando's status as a very large online platform on 3 September 2025, accepting a count of more than 83 million recipients against the retailer's argument that only 30 million used its third-party marketplace.

Whether generative systems belong in the search category was contested until this week. Commission spokesperson Thomas Regnier had said the treatment of large language models would be decided case by case, according to TechRepublic, while commentary published on Verfassungsblog in March 2026 argued that a functional reading of Article 3(j) was legally required.

Repository quality remains the recurring complaint. The €120 million fine against X on 5 December 2025 cited an advertising database lacking adequate detail on advertiser identity and targeting criteria, alongside researcher access failures, and preliminary findings against TikTok and Meta in October 2025 covered similar ground.

A Commission report published on 17 November 2025 under Article 91(1) concluded that the 45 million threshold remains fit for purpose, a finding critics read as declining to move towards risk-based designation. The regime also stops at the Union's borders: as the EEA explainer sets out, the DSA has not been incorporated into the EEA Agreement, leaving Iceland, Liechtenstein and Norway outside it.

Disambiguation

VLOP covers hosting services that store and disseminate information publicly at a user's request, a label held by Facebook, TikTok and Amazon Store. The two categories share Section 5 but not Articles 16 to 28.

Gatekeeper is a designation under the Digital Markets Act, a competition instrument with different thresholds and duties. Alphabet holds both statuses, which are unrelated in law.

Online search engine without the prefix is a far larger group. Undesignated engines owe points of contact, terms and conditions, transparency reporting and the six-monthly user count, and nothing in Section 5.

Recent developments

The Commission designated ChatGPT as a very large online search engine today, alongside Reddit and Roblox as very large online platforms, taking the top tier to 28 services and placing an AI assistant in the search category for the first time. The Commission treated ChatGPT as a hybrid service qualifying as an online search engine because it responds to prompts and queries, including by searching the web.

OpenAI disclosed that the search function averaged roughly 159 million monthly active users in the Union over the six months ending March 2026, against 57.2 million reported by Reddit and about 48 million by Roblox. Those figures are self-reported, and the ChatGPT number follows an earlier disclosure of 120.4 million for the six months to September 2025. All three have until the end of November to comply.

Henna Virkkunen, executive vice-president for tech sovereignty, security and democracy, said the services would be held to "a higher standard of scrutiny and accountability", according to Euronews. Supervision runs with Coimisiún na Meán for ChatGPT and Reddit and with the Dutch Authority for Consumers and Markets for Roblox. Enforcement has produced roughly €870 million in fines to date, including €550 million against AliExpress on 20 July 2026 and €200 million against Temu in May 2026.

Timeline

  • 15 December 2020: European Commission proposes the Digital Services Act alongside the Digital Markets Act
  • 19 October 2022: Regulation (EU) 2022/2065 adopted
  • 27 October 2022: Published in the Official Journal
  • 16 November 2022: Entry into force
  • 17 February 2023: First deadline for platforms and search engines to publish average monthly active recipients
  • 2 March 2023: Delegated Regulation (EU) 2023/1127 sets supervisory fee methodology
  • 25 April 2023: First designations, covering 17 VLOPs and 2 VLOSEs, Google Search and Bing
  • August 2023: Obligations become binding on the first designated services
  • 27 November 2023: Implementing decisions set 2023 supervisory fees for Facebook, Instagram and TikTok
  • 17 February 2024: Regulation applies in full to all intermediary services
  • 27 May 2025: Stripchat designation revoked after falling below the threshold
  • 3 September 2025: General Court upholds Zalando designation
  • 10 September 2025: General Court annuls 2023 supervisory fee decisions in T-55/24 and T-58/24
  • 17 November 2025: Commission report concludes the 45 million threshold remains fit for purpose
  • 5 December 2025: Commission fines X €120 million in the first non-compliance decision
  • 26 January 2026: WhatsApp designated a very large online platform
  • 20 July 2026: Commission fines AliExpress €550 million
  • 27 July 2026: Consolidated AI Act text routes AI systems inside designated services to the AI Office
  • 31 August 2026: ChatGPT designated a very large online search engine; Reddit and Roblox designated very large online platforms
  • End of November 2026: Compliance deadline for the three newly designated services

Summary

Who: The European Commission designates and supervises very large online search engines. Google Search and Bing held the label from April 2023; ChatGPT joined on 31 August 2026. Digital Services Coordinators, including Coimisiún na Meán in Ireland, cooperate on supervision. Advertisers, publishers, researchers and civil society organisations are the intended beneficiaries of the transparency duties.

What: A designation tier under Regulation (EU) 2022/2065 that triggers Articles 33 to 43: annual systemic risk assessment and mitigation, independent audit, a non-profiling recommender option, a public advertising repository with an API, vetted researcher data access, an internal compliance function, six-monthly transparency reporting and an annual supervisory fee capped at 0.05% of worldwide net income. Fines reach 6% of worldwide annual turnover.

When: The regulation entered into force on 16 November 2022. First designations were adopted on 25 April 2023 and became binding four months later. The full regime applied to all intermediary services from 17 February 2024. The most recent designations were made on 31 August 2026, with compliance due by the end of November.

Where: The 27 member states of the European Union. The regulation has not yet been incorporated into the EEA Agreement, so Iceland, Liechtenstein and Norway sit outside the designation regime.

Why: Search services shape what a large share of the population sees without hosting any of it, a position the pre-existing e-commerce framework did not address. The tier concentrates supervision on services large enough that their ranking and advertising systems carry population-level consequences, and funds that supervision from the companies themselves.