Site Behavior Lab

Baseline visit v1 schema · facts legacy-derived · descriptive report

www.medicare.gov

https://www.medicare.gov/

Jul 27, 2026, 10:26 AM UTC

complete; derived from status and warnings

View site historyScan this exact route againReport an evidence problem

Public corrections ledger · SBL-CORR-2026-001

This report has a reviewed clarification

SBL-CORR-2026-001: The historical input-probe disclosure overstates coverage. Unload-only transmissions were not reliably recorded. Focus and blur handlers could run, and per-field failures were not fully counted. These reports cannot establish absence of input transmission outside their retained observations.

Read the public review record

What this actually means

medicare.gov recorded 128 fewer third-party requests in the visit configured for Brave-list blocking.

SBL-CORR-2026-001: The historical input-probe disclosure overstates coverage. Unload-only transmissions were not reliably recorded. Focus and blur handlers could run, and per-field failures were not fully counted. These reports cannot establish absence of input transmission outside their retained observations.

8tracking-service entities
172cross-site requests
25third-party cookie records
1fingerprint-like pattern
Observed in two automated visits: evidence to check, not a verdict.

Plain-Language Findings

What this visit means

Unfamiliar terms are defined in the glossary
playwright-chromium

Worth checking

Bottom line: this visit has review-worthy signals

The scan observed signals a non-expert should not have to decode from raw request tables.

The cards below translate the evidence into plain language. Where a measured distribution exists, severity ranks this visit against percentiles from the report's exact schema, methodology, tracker-catalog, ServiceRole-taxonomy, metric-contract, producer, and Global Privacy Control cohort, with each percentile card naming its metric-specific measured-site denominator (among 98 sites with a successful load across all cohorts; other methodologies, request-capped visits, and post-choice consent visits are excluded from this denominator, while failed or block-page attempts are outside that coverage), a curated set of popular, mostly commercial sites, not a random sample of the web, and otherwise uses fixed reference thresholds. The request log, domain table, and methodology remain below for verification.

235 requests observed in one controlled visit.

Worth checking

58 requests matched Brave Shields filter lists

58 requests matched the default filter lists of Brave Shields, the ad and tracker blocker built into the Brave browser, while loading normally.

Computed with Brave's own ad-block engine and default filter lists in classification mode: matched requests were not blocked by the scanner and remain in this report's observed request counts. Matching shows what Shields would target on this visit's traffic; an actual Shields visit blocks these and also prevents their follow-on requests, so this number is neither a measured block count nor the total effect.

The hand-curated service catalog separately matched 53 request rows in this visit.Show matched requests

Nothing observed

Lower values observed across comparable metrics in the Brave-list blocking attempt

With the scanner configured to apply Brave's ad-block engine and default Shields filter lists (a simulation in this scanner's browser, not a live Brave-browser visit; application was not verified), this paired visit showed 128 fewer third-party requests, 20 fewer third-party cookies and 43 fewer tracking-related service requests.

Services only seen in the unblocked visit: Google, The Trade Desk and Microsoft, plus 5 others. The blocking visit's engine directly blocked 15 requests; the remaining difference may include follow-on requests that never started once their sources were blocked. A single paired comparison can also reflect run-to-run variance (ad rotation, caching, experiments), so treat this as an observed difference, not a measured blocking rate.

Signed per-metric differences between the two visits; nothing is summed across metrics.Show matched requests

Context

Tracking companies the privacy policy does not appear to name

The Trade Desk, Index Exchange and Magnite, plus 2 others were sent requests during this visit, but the policy text matched none of the names this scan knows those companies by.

Policies often disclose vendor categories rather than company names, so an unnamed vendor is a transparency gap worth reviewing, not automatically a violation. Named in the policy: Google, Microsoft and Tealium.

Policy at https://www.medicare.gov/privacy-policy; 0 checkable statements matched; 3 of 8 observed tracking companies named in the policy.

Worth checking

Catalogued service domains recorded responses during this visit

Google, The Trade Desk and Microsoft, plus 5 others appeared in the request log.

A catalog match identifies a maintainer-reviewed service/domain mapping; it does not establish why an individual request occurred, what it carried, or whether profiling happened. Functional catalog labels include analytics / tag management, advertising and advertising / demand-side platform. This scan could not identify 18 of the 35 third-party hosts recorded here, so it cannot say who operates them. That is a limit of identity coverage, not evidence about the site. The role taxonomy assigns these additional services explicitly non-tracking operational, support, security, consent-management, or hosting roles: New Relic.

172 cross-site requests across 35 third-party hosts.At or above the 75th-percentile mark for third-party domains across the 56 sites measured for this metric. Elevated distinct tracking-service entities count (at or above the 6 reference threshold).Show third-party requests

Context

Requests were dispatched to catalogued major-platform domains

This visit dispatched requests to catalogued domains for Google and Microsoft.

The domain matches identify services, not the requests' purpose, payload, or whether any profile linking occurred.

22 requests to these platforms.Show catalog-matched requests

Nothing observed

Google Analytics present, no remarketing signal

Google Analytics was observed, but no DoubleClick remarketing sync appeared in this visit.

Standard analytics collection was observed, without the stats.g.doubleclick.net advertising sync.

Google Analytics host observed; no stats.g.doubleclick.net request.Show catalog-matched requests

Worth checking

Third-party cookies were present

25 third-party cookies showed up during the visit.

The scanner observed cookie metadata whose domain crossed the scanned site's registrable-domain boundary. This report does not retain cookie values or partition keys, so it does not establish whether a cookie was a persistent identifier or could recognize a visitor across sites.

51 cookies total in this report.At or above the 75th-percentile mark for third-party cookies across the 56 sites measured for this metric.

Worth checking

Offline audio rendering heuristic matched

1 behavioral heuristic matched: Offline audio rendering heuristic.

These heuristics look for behavior patterns such as canvas readback after drawing, repeated canvas font measurement, WebGL entropy reads, offline audio rendering, or WebRTC peer-connection setup. They are review prompts for this visit, not proof of cross-site identity tracking.

1 offline render with audio.OfflineAudioContext.createAnalyser, audio.OfflineAudioContext.createDynamicsCompressor and audio.OfflineAudioContext.createOscillator, plus 1 other

Raw evidence

Open the interactive evidence explorer

The findings above are built from the stored report. Load the request rows, domains, cookies, storage keys, browser signals, visit phases, charts and CSV export when you want to check them; the versioned report JSON is always available below without this interface.

This versioned report is currently retained in the public corpus. Follow the currently retained site history, repeat the same public route when it is available, or request a transparent evidence correction.

Integrity and provenance

Evidence receipt

Open report JSONDownload corrections with this JSONOpen provenance sidecarPrintable versionDownload PDF + evidenceOpen PDF
Report ID
20260727-7f69d9e7baa6825ac7f3c9ae39c2e70c
Site
www.medicare.gov
Latest visit
Schema
v1 schema · facts legacy-derived · descriptive report
Verify recorded provenance

Baseline visit

Started
Run quality
complete; derived from status and warnings
Scanner
playwright-chromium
Browser
149.0.7827.55
Redaction
not recorded by this schema
Provenance
Exact build and instrument digests were not recorded by this legacy schema.

Variant visit

Started
Run quality
complete; derived from status and warnings
Scanner
playwright-chromium
Browser
149.0.7827.55
Redaction
not recorded by this schema
Provenance
Exact build and instrument digests were not recorded by this legacy schema.

Recorded provenance is self-reported measurement metadata, not a cryptographic attestation. The public versioned report JSON contains the retained public evidence; see the methodology for interpretation and retention limits.

This report covers what the scanner measures, not everything a site can do. 16 browser surfaces are not instrumented at all (Every page except the one that was scanned; Anything that only loads after scrolling or interaction; Why a request happened, as a causal chain; and 13 others), 3 capabilities are declined by policy, and 3 are outside what any single visit can see. Their absence from this report is not evidence that they did not occur. Read the published coverage boundary.

Detector accuracy is unmeasured. No calibration study currently publishes a precision or recall for the detectors on this page, so a detector match here is a recorded observation, not a calibrated classification. How detector accuracy is measured.

Approved use boundary: This report is investigative evidence that requires independent corroboration. It is not a standalone legal determination and not the sole exhibit in a legal proceeding. Recorded in this project's release manifest on .