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Assessed Signals

Opportify evaluates dozens of signals across multiple intelligence sources to produce a composite risk score. This page documents the baseline categories of signals we can assess. The actual signals evaluated for any given request depend on the inputs you provide — for example, email signals are only assessed when an email address is included, and behavioral signals require the JS Script integration.

Continuously Evolving

Our signal library is dynamic and continuously expanding. The signals listed here represent the foundational categories we evaluate. We regularly add new detectors, refine scoring weights, and introduce novel signal sources without requiring any changes on your end.

For security reasons, we do not disclose the full list of signals, internal scoring weights, or detection thresholds. Publishing every signal in detail would give fraudsters a blueprint to evade detection. Our goal is transparency about what we assess, while keeping how we score it unpredictable to adversaries.


Risk Score Overview

Every analysis produces a risk score ranging from 200 (lowest risk) to 1000 (highest risk), along with a human-readable risk level:

Score RangeLevelInterpretation
≤ 300lowestVery low risk — likely legitimate
301–400lowLow risk — minor signals present
401–600mediumModerate risk — warrants review
601–800highHigh risk — likely fraudulent
> 800highestVery high risk — strong fraud indicators

The final score is a weighted composite of signals from six intelligence sources: email, IP, content, session (behavioral), velocity, and geographic consistency.


Email Intelligence Signals

Assessed when an email address is provided.

Deliverability & Mailbox

SignalDescription
SMTP verificationReal-time probe to determine if the mailbox exists and accepts mail
Deliverability classificationClassified as yes, no, or unknown
Catch-all detectionWhether the domain accepts mail to any address
Mailbox full detectionWhether the mailbox is over quota
ReachabilityWhether the domain's mail infrastructure is reachable

Domain Classification

SignalDescription
Disposable domain detectionTemporary/throwaway email providers
Free provider detectionWell-known free email services (Gmail, Yahoo, etc.)
Provider identificationResolved email provider name
Email type classificationprivate, free, or disposable

DNS & Authentication

SignalDescription
MX record validationWhether valid mail exchange records exist
SPF record validationSender Policy Framework presence and validity
DKIM configurationDomainKeys Identified Mail selector presence
DMARC validationDomain-based Message Authentication policy
MX relay detectionWhether the domain routes through a relay service
MX relay categorizationsecurity-gateway, alias-forwarder, or transactional-relay

Domain Enrichment

SignalDescription
Domain ageHow long the domain has been registered
Domain expirationExpiry status (expired, expiring soon, recently expired)
Registrar identificationDomain registrar
SSL certificate validityWhether the domain has a valid SSL cert
A record validationWhether the domain resolves to a valid IP
Blocklist statusWhether the domain appears on known blocklists
MTA-STS / BIMI statusEmail security policy indicators

Address Structure

SignalDescription
Plus-addressing (tag) detectionIdentifies user+tag@domain patterns
Role address detectionShared inboxes like info@, support@, admin@
No-reply detectionAddresses matching no-reply patterns
Email correctionMisspelling detection and suggested corrections

Email Risk Factors

When risk is elevated, the top contributing factors are surfaced. Examples include:

instant-bounce · no-mx-or-invalid · disposable-domain · free-provider · blocklisted-domain · new-domain · young-domain · spoofing-risk · domain-expired · domain-expiring-soon · invalid-ssl · catch-all-domain · mailbox-full · missing-auth-spf · alias-forwarder-mx · transactional-relay-mx · tagged-address · role-address · noreply-detected · provider-unknown · deliverability-unknown


IP Intelligence Signals

Assessed when a user IP address is provided.

Connection & Network Type

SignalDescription
Connection type classificationenterprise, wired, mobile, vpn, tor, open-proxy, cloud-provider, satellite
Trusted provider detectionKnown legitimate infrastructure providers
Reverse DNS resolutionWhether the IP has a valid PTR record

Geolocation

SignalDescription
Country, region, cityGeographic location of the IP
Continent & coordinatesBroad and precise location data
TimezoneTimezone associated with the IP
Phone/currency/language codesRegional metadata

WHOIS & Network Registration

SignalDescription
ASN identificationAutonomous System Number and name
Organization detailsRegistered organization for the IP range
RIR sourceRegional Internet Registry (ARIN, RIPE, APNIC, etc.)
Contact recordsAbuse, admin, and tech contacts

Blocklist & Reputation

SignalDescription
Blocklist presenceWhether the IP is flagged on known blocklists
Active abuse reportsNumber of active reports
Blocklist sourcesNumber of independent sources reporting the IP

IP Risk Factors

ip-blocklisted · active-abuse-reports · tor-exit-node · open-proxy · vpn · cloud-hosting · no-reverse-dns · satellite-network · mobile-network · missing-whois · missing-asn · trusted-provider


Behavioral (Session) Signals

Assessed only when the Opportify JS Script is integrated on your pages. These signals are not available for API-only integrations that do not include the client-side script — in those cases, risk scoring relies on the other signal categories (email, IP, content, velocity, and geo).

Bot & Automation Detection

SignalDescription
Automation tools detectionDetects headless browsers, Puppeteer, Selenium, Playwright, and similar tools
Honeypot interactionHidden fields filled by bots but invisible to real users
Bot agent detectionUser agent strings associated with known bot frameworks
User agent consistencyCompares declared UA with actual browser capabilities

Human Interaction Analysis

SignalDescription
Typing speed analysisDetects inhuman typing speeds or absence of typing
Interaction provenanceClassifies input method as legitimate, password-manager, or bot based on event patterns
Form interaction presenceWhether the user interacted with the form at all
Mouse/pointer behaviorDetects stuck or absent pointer movement
Submit timingTime between page load and form submission (instant-submit, rapid-submit)

Device Context

SignalDescription
User agent parsingBrowser, engine, OS, device type, CPU architecture
Screen & viewportResolution, color depth, pixel ratio, orientation
Hardware capabilitiesCPU cores, device memory
Storage APIsLocalStorage, SessionStorage, IndexedDB availability
User preferencesColor scheme, reduced motion, contrast settings
Device fingerprint consistencyDetects drift between sessions

Session Behavioral Factors

honeypot · automation-tools · typing-speed-anomaly · suspicious-mouse · device-drift · sdk-ua-mismatch · content-gibberish · instant-submit · rapid-submit · no-device-fingerprint · no-form-interaction · multiple-pageloads · automation-hint · password-manager-fill

content-gibberish vs Content Analysis

content-gibberish in the session factors refers to real-time client-side detection of gibberish-like typing patterns as the user interacts with the form. The Content Analysis section below covers server-side post-submission text analysis on the final field values. Both contribute to the overall score independently.


Content Analysis Signals

Assessed on text fields (names, subject, message) submitted with the form.

SignalDescription
Gibberish detectionScores text fields for random/nonsensical character patterns
Spam content detectionIdentifies common spam patterns in message content

Content is analyzed independently per field (names, subject, message) with individual gibberish and spam scores.


Velocity Signals

Assessed across submission history for the same identifiers.

SignalDescription
Short-window frequencySubmissions within 1-minute and 5-minute windows
Medium-window frequencySubmissions within a 1-hour window
Long-window frequencySubmissions within a 24-hour window
Anomaly detectionFlags when frequency exceeds adaptive thresholds

Geographic Consistency Signals

Cross-references geographic data from multiple sources to detect inconsistencies.

SignalDescription
IP country vs. declared countryCompares the IP's geolocation with user-provided country
Email domain countryCountry associated with the email domain
Phone country codeCountry derived from phone number prefix
Session countryCountry from session/device context
Consistency scoreOverall geographic alignment assessment

Why We Don't Disclose Everything

We intentionally withhold some details about our signal assessment:

  1. Security through unpredictability — Publishing every signal and its exact weight would allow adversaries to craft submissions that specifically evade each check. By keeping parts of our detection logic opaque, we maintain an information asymmetry that works in your favor.

  2. Continuous improvement — Our team constantly ships new detectors and adjusts scoring models based on emerging fraud patterns. Documenting every internal change would be impractical and would create stale documentation that misleads integrators.

  3. Responsible disclosure — Certain detection techniques are more effective when their existence isn't publicly known. Once a technique is documented, sophisticated attackers will attempt to circumvent it.

What we commit to: transparency about the categories of signals assessed, clear API response documentation, and actionable risk factors in every response so you always understand why a submission was scored the way it was.