Built on ACFE analytics · Aligned with ICAI SA 240 and the Standards on Internal Audit
Expense registers are large, repetitive and mostly honest. That is exactly why the unusual is hard to see: a duplicate sits in a different report, an approval sits inside a forwarded e-mail, a bill is shared between two claims, a cost centre drifts for six months. A reviewer reading claim by claim cannot see across tens of thousands of lines. A sample cannot either.
Every claim line sits in exactly one row: a bill is attached and matches; a bill is attached but cannot be confirmed; no bill, but the claim is paid by formula (such as kilometres) and is tested that way; or no bill at all. The rows add up to the register total, and a check cell reads zero. If the numbers ever stop adding up, you see it.
“Matches the bill” means the amount on the paper equals the claim. It does not mean the claim is right.
Group names follow the expense-reimbursement scheme classes in the ACFE Fraud Tree.
We also retire tests that do not hold up. In our own pilot we removed or narrowed several that raised false alarms, for example treating two colleagues who share a hotel bill as a duplicate.
The register already says who spent, where and under whom. CORAA uses all of it: spend, people, spend per head, field-work share and month-by-month trend for every company, zone, department, section, cost centre, work location and grade. A unit is called out only when it spends at least twice what its own department’s people at the same grades normally spend, with enough people and rupees to matter. That keeps a field-sales team from being flagged just for travelling more than head office.
An honest limit. Intelligence compares spend with expectation and with peers. It does not compare with revenue or budget unless you give us those.
Approval e-mails are often forwarded, quoted or printed inside another document. CORAA uses small language models to read them, and then checks every answer against the text: the quote must be in the document, the person must be named in it, an “approved” must be in the newest message, and the approver cannot be the person who asked. An answer that fails the check is shown to a person as “needs a look”. It is never turned into a finding.
We align with these standards and references. We do not claim compliance with them, and we say plainly what we did not do.
| Area | What we use it for | Authority and reference | Status |
|---|---|---|---|
| Classifying schemes | Grouping tests by how expense fraud happens | ACFE Occupational Fraud Classification (expense reimbursement schemes) Reference | Used |
| Analytics tests | Repeated claims, round amounts, Sunday claims, outliers, missing information | ACFE Anti-Fraud Data Analytics Tests Reference | Used |
| Threshold behaviour | Claims held just under a receipt or approval limit | ACFE red flag; Loss Prevention Media (secondary source) Reference | Used |
| First-digit test | Context on how amounts are distributed | Nigrini, Benford's Law: Applications for Forensic Accounting, Auditing, and Fraud Detection (Wiley, 2012); Drake and Nigrini (2000) Reference | Context only |
| Fraud-risk thinking | Why we test approvals, concentration and override-style patterns | ICAI SA 240 (equivalent to ISA 240); ICAI SIA 11, Consideration of Fraud in an Internal Audit Reference | Context only |
| Analytical procedures | Comparison with peers and with expectation | ICAI SIA 6, Analytical Procedures (legacy numbering still listed by ICAI) Reference | Used |
| Evidence and sampling | Treating bills and e-mails as evidence, and how much is read by eye | ICAI SIA 320 (formerly SIA 10), Internal Audit Evidence; SIA 5, Sampling | Used |
| GSTIN | Format and check-character test on supplier tax numbers | GSTIN structure of 15 characters (state code, PAN, entity number, “Z”, check character). Secondary guides; the official GSTN check-digit algorithm has not been independently verified | Used |
| File metadata | Photo capture date, creating software | EXIF (CIPA DC-008); PDF information dictionary (ISO 32000) | Used |
| Our own validation | Recounting from the raw file, shifted-date control, reading hits by eye, answer key for the AI reader | CORAA validation practice | Used |
Send us one expense register and its attachments. We will show you the proof ladder, the leads, the intelligence by company and zone, and the standards behind each, so your team can decide what to put into regular use.
Findings are leads for your team to confirm against the original document and the employee’s explanation. They are not conclusions and not an audit opinion.