Microsoft

The US government said Microsoft used its control of Windows to crush browser competition—especially Netscape—by bundling Internet Explorer and pressuring PC makers. Courts agreed Microsoft broke competition rules in important ways. The company was not broken up, but it had to change how it treated partners and rivals for years.

Outcome: Liability findings; settlement/consent decree with behavioral remedies (API disclosure, OEM flexibility).

Microsoft bought Activision Blizzard, home of Call of Duty and World of Warcraft, for roughly $69 billion. Regulators worried Microsoft might make those games exclusive to Xbox or its cloud service. The UK initially said no, then yes after Microsoft promised to license games to other cloud platforms. The US FTC failed to stop the deal in court, and the EU cleared it with conditions. Gamers still see Call of Duty on PlayStation—for now, under negotiated deals.

Outcome: Deal closed after UK CMA initially blocked then accepted restructured cloud licensing remedies; FTC preliminary injunction denied though administrative case continued separately.

When Microsoft bought Activision, most attention was on PlayStation vs Xbox. Britain's antitrust agency cared more about cloud gaming—playing high-end games streamed over the internet. It first blocked the deal, fearing Microsoft would hoard Activision hits on its own cloud service. Microsoft then promised to license those games to other cloud platforms for 15 years, and the UK approved. It is a short case study in remedy-driven clearance.

Outcome: April 2023 prohibition decision; October 2023 clearance after cloud content licensing undertakings; deal completed globally.

Europe fined Microsoft for bundling Windows Media Player into Windows, saying PC dominance let Microsoft crush rival media software. Microsoft had to offer a stripped-down Windows without the player—though few consumers chose it. The case paired with later EU action over Internet Explorer and helped define how Europe treats software tying.

Outcome: 2004 decision fined Microsoft and ordered a version of Windows without Media Player ('Windows XP N'); later EU browser choice remedy followed in a related strand.

Europe is investigating whether Microsoft illegally bundled Teams video chat into Office subscriptions, making it hard for Slack and others to compete. Microsoft now sells Office without Teams in many markets and cut prices—but the EU probe is not closed. No fine or final ruling yet.

Outcome: On 12 September 2025 the Commission made Microsoft's Article 9 commitments binding in AT.40721 and AT.40873. Microsoft must offer EEA suites without Teams, with switching, interoperability, and data portability. Core duties last seven years; interoperability and portability last ten. Slack and alfaview withdrew their complaints.

Europe's Digital Markets Act treats the biggest tech platforms like regulated utilities: they must open doors they used to lock. Apple, Google, Meta, Amazon, Microsoft, and others must offer more choice in app stores, messaging, search defaults, and data sharing. Regulators are still checking whether the changes work—or whether companies comply only on the surface.

Outcome: Designations and core obligations are in force; compliance dialogues, DMA Article 29 market investigations, and potential fines remain active. No final closure of oversight.

Most companies rent computing power from a few giant clouds—Amazon AWS, Microsoft Azure, and Google Cloud. The FTC is asking whether those providers make it artificially hard to leave or to run popular software on a competitor's servers. The review is ongoing; no final US case has concluded.

Outcome: Information gathering and staff analysis continue; no public enforcement decision or court ruling has concluded the inquiry.

Big Tech funded AI startups through partnerships instead of classic mergers. The FTC wants to know whether those deals secretly block competition for chips, data, and engineers. This is an inquiry—a fact-finding step—not a ruling that AI partnerships are illegal.

Outcome: Mandatory orders to major players are pending analysis; no enforcement action or court judgment has concluded the inquiry.

Cloud gaming lets you play console-quality games on a phone by streaming from remote servers. Apple historically kept cloud gaming apps off iPhones or forced cumbersome workarounds. Europe's DMA and antitrust reviews ask whether that blocked competition. Access is improving in the EU, but enforcement is not finished.

Outcome: DMA browser and app distribution duties apply; cloud gaming-specific abuse probes and developer disputes continue without final EU-wide remedy.

Most of Europe’s apps and company systems run on a few US clouds. In November 2025 EU regulators opened Digital Markets Act investigations into Amazon’s AWS and Microsoft’s Azure—asking whether lock-in fees, licences, and technical walls make switching or using rival software too hard. No fine yet.

Outcome: Investigations opened November 2025. No infringement decision or fine yet. Parallel work continues under the Data Act and classic Article 102 theories.

The FTC is investigating Microsoft's cloud licenses and its OpenAI tie. As of mid-2026 it had sent demands for documents and had not sued.

Outcome: Civil investigative demands went to Microsoft and to competitors. As of reporting in June 2026, the agency had not filed a lawsuit. An investigation is not a charge.

Britain investigated the big cloud providers and moved the issue into its new conduct-rules system. That follow-on work was still open in 2026, beside a separate EU look at AWS and Azure.

Outcome: The market investigation's findings fed SMS work rather than a one-time fine. EU DMA cloud investigations of AWS and Azure are a parallel file. Neither had produced a final conduct code that ended the issue by October 2026.

Europe said Microsoft hoarded the technical secrets that let other companies' servers talk to Windows networks—abusing its dominance. Microsoft fought for years, paid massive fines, and was penalized again for dragging its feet on fixes.

Outcome: 2004 decision fines and disclosure duties; additional €899 million penalty for non-compliance in 2008; later interoperability commitments.