Public competition mandate
Policy proposals informed by public competition research. Concentration can identify a question worth investigating; it does not establish harm or unlawful conduct.
The role of government is not passive refereeing. It is to protect people from private bottlenecks, hidden gatekeepers, and markets where choice exists only on paper.
Public action triage
The focused market stays first. Screening rank orders attention; it does not measure public harm or establish liability. The agency guideline and Antitrust Radar priority queue remain separate below. Every docket keeps its evidence boundary and government-action lane visible.
FTC/DOJ
People exposed
Users, publishers, and small businessesDefaults, distribution control, and data lock-in can make switching technically possible but practically weak.Government lever
FTC/DOJ conduct reviewTest defaults, exclusionary distribution, data access, and interoperability remedies against public outcomes.Evidence boundaryAgency-ready source trail and market-definition caveats · estimated public · medium confidence
12
profiles
7
HHI >= 2,500
4
data gaps
45
sources
Public duty compact
Evidence to action
Action packet contract
Profile, sources, data, and brief stay linked before anyone sends an ask.
Public duty compact
Public action triage
Public action triage
The focused market stays first. Screening rank orders attention; it does not measure public harm or establish liability. The agency guideline and Antitrust Radar priority queue remain separate below. Every docket keeps its evidence boundary and government-action lane visible.
FTC/DOJ
People exposed
Users, publishers, and small businessesDefaults, distribution control, and data lock-in can make switching technically possible but practically weak.Government lever
FTC/DOJ conduct reviewTest defaults, exclusionary distribution, data access, and interoperability remedies against public outcomes.Evidence boundaryAgency-ready source trail and market-definition caveats · estimated public · medium confidence
Public market launcher
Browsers
Software
3,612
HHI
Search engines
Digital platforms
7,359
HHI
Mobile operating systems
Digital platforms
5,337
HHI
Social referrals
Digital platforms
4,995
HHI
01
Start with the lived market people can actually choose from.
02
Show publisher, date, method, and confidence before making claims.
03
Turn evidence into oversight, disclosure, and fair-market rules.
Public record
>1,800
DOJ/FTC Merger Guidelines (2023)
2023 guideline HHI threshold
The agencies' 2023 Merger Guidelines treat markets above this HHI level as highly concentrated.
~80%
FTC-backed PBM profile
PBM prescriptions
The FTC reported the top three PBMs processed nearly four in five U.S. prescriptions in 2023.
49.7%
U.S. Census Bureau
renter cost burden
Census reported nearly half of U.S. renter households spent more than 30% of income on housing costs in 2023.
1.1%
Census HVS Q1 2026
housing vacancy
Census HVS reported a 1.1% homeowner vacancy rate in Q1 2026, a scarcity signal that strengthens the case for local competition evidence.
Government duty queue
Record-to-duty route
Action brief station
The public workflow should start near the top: pick a priority market, inspect the source trail, open the data console, and generate a government-ready brief.
Market in focus
Browsers
People harmed
United States
Government lever
Test whether the dominant firm controls access, switching, pricing, defaults, distribution, or other chokepoints that weaken consumer choice.
HHI 3,612 should move into a public ask that names the affected users, the missing record, and the agency route.
3/3 core metrics; disclose source and confidence limits
Source to action route
HHI
3,612
HHI 3,612
CR4
93.8%
four-firm share
Top firm
50.0%
single-firm share
Review lane
Immediate review
estimated public · medium confidence
This station makes the advocacy route inspectable before the longer docket: profile, source rows, public data, then a brief people can send to government.
Government duty ledger
This ledger turns the mission into a government work plan: disclose hidden market facts, scrutinize bottlenecks, investigate public harm, and publish reusable evidence.
Public duty route
Evidence moves from data gaps to public obligations.
When public records do not show firm shares or local control, government should require disclosure before people are asked to trust the market.
Published HHI at or above 2,500 should trigger harder questions about switching costs, entry barriers, platform leverage, and whether choice exists in practice.
The action docket turns market evidence into public questions agencies, legislatures, and local officials can inspect.
Every public ask should carry citations, dates, confidence labels, and open data routes so others can challenge or reuse the evidence.
Public action docket
The docket keeps the mission operational: identify where concentrated power harms people, show what evidence is public, name the agency lane, and make the next ask inspectable.
7
markets meeting the published structural review screen
1
markets where concentration or trend signals need continuing pressure
4
markets where the public record is too thin for firm-level accountability
4
profiles where public evidence must be disclosed before claims harden
Evidence-to-action route
Choose the stage that matches the public decision, then inspect the ranked market docket below.
Evidence question
What can the public record prove today?Test whether the dominant firm controls access, switching, pricing, defaults, distribution, or other chokepoints that weaken consumer choice.
Public harm
Users, publishers, and small businesses
Defaults, distribution control, and data lock-in can make switching technically possible but practically weak.
Government lever
FTC/DOJ conduct review
Test defaults, exclusionary distribution, data access, and interoperability remedies against public outcomes.
Evidence pressure: HHI 3,612
Test whether the dominant firm controls access, switching, pricing, defaults, distribution, or other chokepoints that weaken consumer choice.
Public harm
Users, publishers, and small businesses
Defaults, distribution control, and data lock-in can make switching technically possible but practically weak.
Government lever
FTC/DOJ conduct review
Test defaults, exclusionary distribution, data access, and interoperability remedies against public outcomes.
Evidence pressure: HHI 7,359
Test whether the dominant firm controls access, switching, pricing, defaults, distribution, or other chokepoints that weaken consumer choice.
Public harm
Users, publishers, and small businesses
Defaults, distribution control, and data lock-in can make switching technically possible but practically weak.
Government lever
FTC/DOJ conduct review
Test defaults, exclusionary distribution, data access, and interoperability remedies against public outcomes.
Evidence pressure: HHI 5,337
Test whether the dominant firm controls access, switching, pricing, defaults, distribution, or other chokepoints that weaken consumer choice.
Public harm
Users, publishers, and small businesses
Defaults, distribution control, and data lock-in can make switching technically possible but practically weak.
Government lever
FTC/DOJ conduct review
Test defaults, exclusionary distribution, data access, and interoperability remedies against public outcomes.
Evidence pressure: HHI 4,995
Test whether the dominant firm controls access, switching, pricing, defaults, distribution, or other chokepoints that weaken consumer choice.
Public harm
Users, publishers, and small businesses
Defaults, distribution control, and data lock-in can make switching technically possible but practically weak.
Government lever
FTC/DOJ conduct review
Test defaults, exclusionary distribution, data access, and interoperability remedies against public outcomes.
Evidence pressure: HHI 4,804
Transparency demand
Opaque summaries are not enough. Public-interest competition work needs citable firm-level data, source dates, methods, and uncertainty labels so advocates can inspect the evidence.
Market in focus
Browsers
HHI 3,612
Publish firm-level market shares where legally possible.
Source records with publisher, access date, citation, and license notes.
Data-status labels that separate verified, estimated, incomplete, and unavailable values.
Public API endpoints that let others audit the underlying tables.
Publish firm-level market shares where legally possible.
Separate aggregate 'Other' rows from firm-level shares.
Release machine-readable tables alongside agency reports.
Source records with publisher, access date, citation, and license notes.
Data-status labels that separate verified, estimated, incomplete, and unavailable values.
Public API endpoints that let others audit the underlying tables.
Publish firm-level market shares where legally possible.
Separate aggregate 'Other' rows from firm-level shares.
Release machine-readable tables alongside agency reports.
Action packet
Target market
Browsers
Public signal
HHI 3,612
Government ask
Publish firm-level market shares where legally possible.
Evidence route
medium confidence · estimated public · Agency-ready source trail and market-definition caveats
Packet completion
Ready with caveats
4/6 checks ready
Markets where concentration signals, data gaps, or public harm narratives deserve fast public review.
7
Immediate
4
Evidence build
4
Data gaps
Select a screened market and audience. The builder creates a short public comment scaffold with the signal, source posture, data gap, and government ask kept together.
Market
define scope
Evidence
source trail
Ask
government duty
Action
public packet
Evidence route
HHI
3,612
HHI 3,612
CR4
93.8%
four-firm share
Top firm
50.0%
single-firm share
Review lane
Immediate review
screening classification
Citable line
Browsers: HHI 3,612; CR4 93.8%; top-firm share 50.0%; medium confidence; estimated public.
Screened market
Audience
Submission route
3/3 core metrics; disclose source and confidence limits
Scope
Software
United States
Government target
Federal
open a public competition inquiry
Source posture
medium confidence
estimated public
Generated packet
To: DOJ, FTC, and sector regulators Subject: Public competition evidence request for Browsers Antitrust Radar flags Browsers as immediate review because the public signal is HHI 3,612. The current public record shows HHI 3,612, CR4 93.8%, and top-firm share 50.0%. Public ask: Test whether the dominant firm controls access, switching, pricing, defaults, distribution, or other chokepoints that weaken consumer choice. Recommended action: open a public competition inquiry. Require the evidence needed to make this market inspectable: Agency-ready source trail and market-definition caveats Source posture: medium confidence; estimated public. This packet is public education and advocacy research, not legal advice.
Audience
DOJ, FTC, and sector regulators
open a public competition inquiry
Signal
HHI 3,612
Immediate review · medium confidence
Evidence need
Agency-ready source trail and market-definition caveats
medium confidence; estimated public
Guardrail
Public education
Review sources and rules before external submission.
Copy the public comment, cite the market signal, open the API route, or seed a notebook with the same selected market.
Notebook starter
const profile = await fetch("/api/public/markets?market=us-browser-usage").then((response) => response.json());
const observations = await fetch("/api/public/observations?market=us-browser-usage").then((response) => response.json());
const sources = await fetch("/api/public/sources?market=us-browser-usage").then((response) => response.json());
console.table(profile.rows);
console.table(observations.rows);
console.table(sources.rows);This is a public education scaffold for advocacy work. Review sources and jurisdiction-specific rules before submitting anything externally.
Policy pressure starts with citations, data status, confidence labels, and market-definition limits.
Open sourcesHHI, CR4, and top-firm share are screens. They are strongest when readers can see what was included and what was withheld.
Review methodsReports should name the data needed, the competition concern, and the public agency or process that can respond.
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Antitrust Radar publishes public education and advocacy research. It does not provide legal advice.