Fake Tax Document Detection API
HTPBE is a REST API that detects forged and tampered tax documents. It works on the binary PDF structure, so the same endpoint handles every regional tax form — W-2 and 1099 in the US, P60 and P45 in the UK, T4 in Canada, Form 16 and ITR receipts in India, payroll tax forms in the EU, and standard tax returns worldwide.
Tax forms look the same after they are edited. The file structure does not. From $15/mo. No sales call.
How Tax Document Fraud Shows Up in the File
Every PDF carries hidden evidence of its history. Here is what to look for.
Edited employer payroll forms (W-2, P60, T4)
Real W-2s, P60s, and T4s come from payroll software — ADP, Paychex, Sage, Xero, and similar. When a fraudster edits values in a consumer PDF tool, the producer field changes from the payroll system to the editor. The API flags this producer mismatch as a high-confidence fraud marker.
Self-built 1099s and freelance income forms
Fake 1099-MISC and 1099-NEC forms used to inflate self-employment income are usually rebuilt in Excel and exported to PDF. The producer field exposes the spreadsheet origin instead of the legitimate IRS-form generator. Multiple revision layers and inconsistent fonts add structural evidence.
Tampered tax returns and assessment notices
Tax return PDFs, ITR receipts, and Notice of Assessment documents are often modified to inflate declared income for loan applications. Each edit appends an incremental update section to the cross-reference table. The API counts revision layers and returns the exact number detected.
Forged signatures on tax declarations
Some tax documents carry the issuing authority’s digital signature — HMRC, IRS e-file confirmations, EU national tax portal exports. If the signature was removed, replaced, or invalidated by post-signing edits, the API returns SIGNATURE_REMOVED or MODIFICATIONS_AFTER_SIGNATURE markers with certain confidence.
The Easy Way: Use HTPBE?
All checks run automatically in seconds — no technical knowledge required.
One API for every tax form, every country
POST the document URL to /api/v1/analyze. The API does not need to know whether the file is a W-2, P60, T4, or Form 16 — it analyzes the universal PDF structure. The same integration covers every regional tax form your underwriting team sees.
Return verdict with named markers
The response includes status (intact / modified / inconclusive), confidence (certain / high / none), and named markers describing each finding. KNOWN_EDITOR_IN_PRODUCER, DIFFERENT_DATES, and MODIFICATIONS_AFTER_SIGNATURE are the most common markers on tampered tax documents.
Block or escalate at the application layer
Use the verdict to gate the application: intact documents proceed automatically, modified documents trigger enhanced review, and the HTPBE check ID is stored in the application record for audit purposes.
Frequently Asked Questions
Which tax forms does the API support?
Any tax document submitted as a PDF is supported. The API has been used on US W-2 and 1099 forms, UK P60 and P45, Canadian T4 and NOA, Indian Form 16 and ITR-V receipts, and EU national tax authority exports. Because the analysis runs on the PDF binary structure, no document-type configuration is needed — the same API call handles every regional form.
Can it tell the difference between a real and a fake tax form?
The API answers a more precise question: was this specific PDF file modified after it was issued? A fake tax form built from scratch in Excel will be flagged because the producer field exposes the spreadsheet origin. A real tax form that was edited will be flagged because the modification creates structural evidence — timestamp gaps, additional revision layers, and producer fingerprint changes. Fully synthetic documents that were never real are a different problem and require visual or AI-based detection methods.
How is this different from IRS or HMRC verification APIs?
Government verification APIs check whether a tax document number exists in the issuing authority’s database. They do not check whether the specific PDF file submitted has been altered. A fraudster can have a valid tax document number on an altered PDF — it would pass a database lookup and fail HTPBE’s structural analysis. Use both: government APIs for existence verification, HTPBE for file integrity.
What confidence level does the API return on tax documents?
Tax documents tend to produce high-confidence markers because they originate from a small set of well-known payroll and tax software vendors. When the producer field is inconsistent with the document type, the marker is unambiguous. When a digital signature was applied (common on EU and government-issued tax PDFs) and was later invalidated, the confidence is certain.
Pricing
Self-serve plans. No sales call, no procurement process.
Starter
$15/mo
30 checks/mo
Manual spot-checks and integration testing
Growth
$149/mo
350 checks/mo
Active document processing pipelines
Pro
$499/mo
1,500 checks/mo
High-volume automation and API integrations
Enterprise (unlimited, on-premise available) — see full pricing and docs
API key on signup. Free test environment on every plan. No card required.
Who uses this in production
The same detection engine, framed for the teams that rely on it.
Fake W-2 Detection (US)
Dedicated detection of forged W-2 wage forms in US lending and tax workflows.
Fake 1099 Detection (US)
Self-employment income fraud — falsified 1099-MISC and 1099-NEC forms.
Fake P60 Detection (UK)
End-of-year UK pay summary forgeries used to inflate declared income.
Fake P45 Detection (UK)
UK leaver-statement fraud submitted in lending and rental applications.
Fake T4 Detection (CA)
Canadian payroll T4 statement forgeries — structural detection.
Fake NOA Detection (CA)
Notice of Assessment fraud in Canadian mortgage and credit applications.
Fake Form 16 Detection (IN)
Indian salary TDS form fraud detected through PDF structure.
Fake ITR Detection (IN)
Income Tax Return receipt forgeries in Indian lending workflows.