The takeaway: This week the EU ordered Google to open Android to rival AI assistants and share search data with competitors — and the legal instrument behind it wasn't a traditional antitrust case. It was the Digital Markets Act, or DMA. If you follow AI at all, you're going to keep hearing those three letters, because the EU has started pointing this particular weapon at the AI layer. Here's what the DMA actually is, how it works, and why it's quietly becoming one of the most consequential forces shaping how AI reaches you.

What the DMA is — and how it's different

The DMA is a European Union law — applicable since 2023, with its obligations on the biggest platforms biting from March 2024 — that regulates the handful of tech platforms big enough to act as "gatekeepers" between businesses and consumers. Its core innovation is timing. Traditional antitrust is ex-post: a regulator watches a company harm competition, spends years building a case, and punishes it afterward — by which point the market has often already tipped. The DMA is ex-ante: it writes a list of things gatekeepers simply may not do, in advance, and applies them across the board. No years-long case required. If you're a gatekeeper, the rules are the rules.

That shift — from "sue them after the damage" to "set the rules before" — is the whole point, because in platform markets, by the time an antitrust case concludes, the winner has usually already won.

Who counts as a "gatekeeper"

You don't volunteer. The Commission designates gatekeepers by hard thresholds — very large EU turnover or market value, plus a "core platform service" (a search engine, app store, operating system, messaging app, browser, and so on) with a big, entrenched user base. In practice that has meant the usual names: Alphabet, Amazon, Apple, Meta, Microsoft, ByteDance, and a few others. Designation is what flips on the obligations.

What gatekeepers must (and must not) do

The DMA's rules read like a list of the specific tricks dominant platforms have used to stay dominant:

• No self-preferencing — a gatekeeper can't rank its own products above rivals' in its own search results or store.
• Interoperability — it must let others plug in: messaging apps must open up, and, as of this week, Android must let rival AI assistants use the same system-level hooks Google reserved for its own.
• Data portability and access — business users can get at the data they generate, and, increasingly, rivals can request access to data that entrenches the gatekeeper's advantage.
• No forced bundling or lock-in — users must be able to uninstall pre-loaded apps, change defaults, and choose alternatives.
• Let business users reach customers directly — no blocking companies from telling users about cheaper options elsewhere.

The teeth

This is why gatekeepers take it seriously: DMA fines run up to 10% of a company's total global annual turnover, and up to 20% for repeat offences — not 10% of European revenue, or of the relevant product line, but of everything, worldwide. For a company Google's size that is a genuinely enormous number. The Commission can also impose behavioural fixes and, in the extreme, structural ones. Combined with the ex-ante design, that makes ignoring the DMA far riskier than slow-walking a conventional antitrust case.

Why it now matters for AI

Here's the part that makes the DMA an AI story and not just a tech-regulation footnote. The law was written for search engines, app stores, and browsers — but its gatekeeper framework is general enough to stretch. This week's Google order is the EU using that existing framework to pre-empt a monopoly in AI assistants, at the exact moment every platform is racing to make its assistant the default gateway to everything. The reasoning is straightforward: the same dominance that let Google own search could let it own the AI assistant on your phone, so the DMA is being pointed there before that position hardens.

Expect more of this. As AI assistants, agents, and app-store distribution of AI become the battleground, the DMA is the tool the EU already has — no new law required — to force the incumbents to share the road.

The honest caveats

It isn't a settled win for anyone. Gatekeepers argue — as Google did this week — that forced openness undermines privacy and security, and that's not purely self-serving: opening system-level hooks genuinely does expand the attack surface, and that tension is real. Critics also warn the DMA can be blunt, treating very different products with one rulebook. Supporters counter that ex-ante rules are the only thing fast enough for markets that tip in months. Both are right about something. What's not in doubt is that the DMA has become the most muscular lever any government currently holds over how the biggest platforms — and now their AI — reach the public.

For this week's news peg, see Sunday's Daily Update on the EU's Android/AI-assistant order.