Brazil-based browser maker Opera has lodged a formal antitrust complaint with Brazil’s competition regulator CADE, alleging that Microsoft unfairly promotes its Edge browser through mandatory pre-installation and design practices that disadvantage rival browsers. The move reignites Opera’s long-standing battle with Microsoft over browser dominance.
Opera asserts that Microsoft is blocking fair competition by denying pre-installation opportunities to other browsers, steering users toward Edge via dark design patterns, and incentivizing PC manufacturers to ship devices exclusively with Edge pre-loaded. Opera claims Brazil—a market where it holds nearly 7% share—is strategically chosen to spotlight global anti-competitive conduct by Microsoft.
Historical Context & Prior Complaints
Opera’s legal action against Microsoft dates back to 2007, when it filed a European Commission antitrust complaint over bundling Internet Explorer with Windows, leading to a €561 million fine. More recently, Opera contested the EU’s decision not to designate Microsoft Edge as a gatekeeper under the Digital Markets Act (DMA), arguing that Edge benefits from unfair preferential access within Windows.
Key Allegations Against Microsoft
- Default pre-installation: Microsoft allegedly requires PC OEMs to supply devices with Edge pre-installed and set as the default browser.
- Dark patterns & misleading UI: Opera claims Microsoft displays pop-ups, banners, and design cues that steer users back to Edge—particularly when users try to download competing browsers like Opera.
- Incentives tied to Windows S Mode: OEM rebates are said to be contingent on shipping devices with Windows in “S mode,” further locking out alternative browser choices.
Opera is urging CADE to enforce remedies, including allowing rival browsers pre-installation, banning coercive design tactics, and restoring real user choice.
Implications & What’s at Stake
- Brazil as Test Case: With Opera holding ~6.8% browser share—Edge at ~11.5% and Chrome dominating with ~75%—Brazil is viewed as a significant test case for global browser competition.
- Regulatory Reach: Opera’s global push may pressure regulators in the EU, U.S., and elsewhere to reconsider how browser markets are structured and defaulted.
- User Experience & Fair Competition: If successful, Opera hopes the complaint could lead to mandates ensuring browser choice, easier installations, and elimination of deceptive UI nudges.
Community & Analyst Views
Vivaldi, Waterfox, Wavebox, and web advocacy groups recently backed Opera’s claims, urging EU regulators to designate Edge as a gatekeeper under the DMA. They argue that Edge’s default placement in Windows makes it a privileged distribution channel that undercuts competition on merit.The Verge
Online users have likewise criticized Windows 11 and Edge for making default-app settings increasingly cumbersome—praising workarounds but lamenting the friction involved in switching browsers.
🧠 Summary Table
| Aspect | Details |
|---|---|
| Plaintiff | Opera Software |
| Defendant | Microsoft |
| Allegations | Edge pre-installation, dark patterns, OEM coercion, blocked competition |
| Forum | Brazil’s CADE competition authority |
| Desired Remedies | Pre-install rights for rivals, UI design fixes, OEM freedom |
| Background | Historic EU antitrust case; DMA-related court challenge |
Final Thoughts
Opera’s antitrust complaint in Brazil marks a bold escalation in its global effort to challenge Microsoft’s dominance in the browser ecosystem. By alleging unfair pre-installation practices and manipulative interface designs, Opera aims to restore competition and user choice—spotlighting the need for stronger oversight of Big Tech’s platform control in PC markets.
