No single test catches every counterfeit electronic component. ERAI, the industry body that collects counterfeit part reports, found that of the suspect counterfeit parts reported to it in 2025, 24% passed electrical testing and only 12% failed it. A part that passes electrical test can still be re-marked, recycled or built on the wrong die, so detection works by layering tests that each look at something different: the outside of the package, the materials, the internal structure and the electrical behaviour. This guide shows which test catches which kind of fake, what the latest ERAI data says, and how to decide how much testing a lot actually needs.
Key Takeaways
- Electrical testing alone misses a large share of counterfeits. In ERAI’s 2025 data, 24% of suspect counterfeit parts passed it.
- Active, in-production parts are not safe. 36.15% of parts reported to ERAI in 2025 were still active when the problem was found.
- Programmable logic ICs were the most reported part type in 2025, at more than 15% of reports, in a group with analog, microprocessor and memory ICs that makes up the largest segment.
- The right amount of testing depends on where the lot came from and where it will be used, not on a fixed sample size.
What does the latest ERAI data say about counterfeit components?
ERAI’s 2025 annual report records 748 parts reported, 29.1% fewer than in 2024. Most of that fall comes from one batch of 248 parts reported by the US Government in May 2024. Without that batch the drop is 7.4%. Global semiconductor sales grew by about a quarter over the same year, so reports did not follow sales as they usually do. One possible explanation ERAI gives is that about 35% of the growth came from high-end AI components, which are harder to counterfeit.
Three findings matter most when you are deciding how to test:
- The parts targeted. Programmable logic ICs, analog ICs, microprocessors and memory ICs make up the largest segment. Programmable logic was the single most reported type.
- The age of the part. Obsolete parts are still the most counterfeited (60.02% of reports), but active parts account for 36.15%.
- New targets. 23.37% of the brands reported in 2025 were new to ERAI, and 10.1% of reported parts belonged to brands never reported before.
The usual caveat applies. ERAI’s figures are self-reported by its members and others who choose to report, so they show what is being found and shared, not the size of the whole market. They are still the most useful public view of which parts are being faked and how they are caught. For a programming house the programmable logic finding is a practical one: a counterfeit device that is programmed and then found to be fake wastes the programming time as well as the part.
Which test catches which kind of fake?
The SAE AS6171 test methods standard splits counterfeit detection into a general requirements document and 11 slash sheets, one per technique. The table maps the common types of fake to the techniques that usually reveal them. It is our summary of standard practice, not a quotation from the standard. Buy the slash sheets from SAE for the exact method requirements.
| Kind of fake | What usually gives it away | Technique (AS6171 slash sheet) |
|---|---|---|
| Re-marked or resurfaced part | Surface texture, marking that dissolves or smears, signs of sanding or coating | External visual inspection, remarking and resurfacing tests (AS6171/2) and a heated solvent test |
| Recycled or salvaged part | Worn or re-tinned leads, residue from a previous board, damaged internal wiring | External visual (AS6171/2), X-ray (AS6171/5) and XRF of the lead finish (AS6171/3) |
| Wrong die or cloned device | Die size, bond wire layout and die markings that do not match the genuine part | Radiological (AS6171/5) and delid and decapsulation (AS6171/4) |
| Rejected or out-of-spec stock | Parameters outside the datasheet, failures across temperature | Electrical test (AS6171/7) |
| Parts affected by cleaning or reclaim processes | Ionic residue, poor solderability | Ionic contamination and solderability testing |
AS6171 also has slash sheets for acoustic microscopy (AS6171/6), Raman spectroscopy (AS6171/8), FTIR (AS6171/9), thermogravimetric analysis (AS6171/10) and design recovery (AS6171/11). These are used on disputed or high-risk parts rather than as routine checks. Our guide to the AS6171 standard covers how the pieces fit together.
Why is electrical testing alone not enough?
Electrical testing checks whether a part behaves as the datasheet says, at the conditions you test. It does not tell you whether the part is what the marking claims. A recycled or re-marked device can meet its electrical specification and still be a counterfeit with a shorter remaining life.
ERAI makes the point directly in its 2025 report. Looking at suspect counterfeit parts that had electrical testing plus other testing, it found 24% passed electrical testing and only 12% failed it. It adds that the true share passing is probably higher, because reporters tend to list failures and leave out passes. Its conclusion is that almost a quarter of suspect counterfeits would escape detection if electrical testing were the only check.
How do you decide how much testing a lot needs?
There is no universal sample size. The right level depends on how well you can trace the part and what happens if it fails in service. The ladder below is our suggested starting point, not a requirement of any standard. Your contract, your customer or the standard you work to may demand more.
| Lot profile | Suggested minimum |
|---|---|
| Bought from the manufacturer or an authorised distributor, with full traceability | Incoming inspection of packaging, labels and paperwork |
| Open market, active part, low-risk end use | Add external visual inspection with marking checks, plus sampled electrical test |
| Open market, obsolete or long-lead part | Add XRF and X-ray, and a heated solvent test on markings |
| Any source, safety-critical or high-reliability use (defence, rail, medical, automotive) | Add delid or decapsulation on samples, full electrical test, and a documented test plan agreed against the contract standard |
Two further points apply at every level. Obsolete parts bought on the open market carry the most risk, but the 36.15% figure above means active parts need a plan too. And when parts have no traceability to the original manufacturer, ERAI recommends comprehensive testing for anything going into a high-risk application.
What should a counterfeit test report show?
A pass or fail with no evidence is hard to defend when a supplier disputes it six months later. When you judge a test house or an in-house process, ask whether the report includes:
- the standard and the technique used for each test, such as the AS6171 slash sheet
- how many parts were sampled and how they were chosen
- photographs of every finding, not only the failures
- the pass and fail criteria that were applied
- the part number, lot and date code, so the result can be tied to the delivery
- the scope of any accreditation the lab claims, since accreditation can cover some methods and not others
How does Systemation Euro test components?
Systemation Euro’s counterfeit component testing service covers visual inspection, XRF analysis, X-ray inspection, decapsulation and die analysis, ionic contamination testing, solderability testing, curve trace electrical testing and heated solvent testing. For routine incoming checks we also use the ABI SENTRY system, which sits between a visual check and a full forensic analysis. It handles package types from two-pin passives to BGAs, and keeps photos, PDFs and datasheets attached to each test record so the evidence for a decision stays in one place. Testing is carried out within our ISO 9001:2015 quality system, certified and audited by UKAS. If your contract requires testing to a specific accredited scope, tell us when you request a quote so we can confirm what we can and cannot supply.
Related reading: how counterfeit components enter the supply chain and open market versus franchised distribution.
Frequently Asked Questions
What is the difference between a counterfeit, grey-market and salvaged component?
A counterfeit is a part that is deliberately misrepresented, for example re-marked, recycled or rebranded, and sold as genuine. A grey-market part is genuine stock sold outside the manufacturer’s authorised channels, so it may be authentic but carries less traceability. A salvaged or recycled part has been removed from used equipment, and it becomes a counterfeit when it is sold as new.
How often should incoming components be tested for counterfeits?
Test by risk, not by a fixed interval. Any lot bought outside the manufacturer or its authorised distributors, and any lot going into a safety-critical or high-reliability product, should be tested before use. Lots with full traceability to the manufacturer usually need documentation and packaging checks only.
Can a counterfeit pass initial testing and fail later in the field?
Yes. A re-marked or recycled part can meet its electrical specification at test and still have a shorter life in service. ERAI’s 2025 data found that 24% of suspect counterfeit parts passed electrical testing, which is why layered testing is used.
Are active, in-production parts safe from counterfeiting?
No. In ERAI’s 2025 data, 36.15% of reported parts were active and available from authorised channels when the problem was found, and 10.1% belonged to brands that had never been reported before.
Can I report a suspect counterfeit part?
Yes. ERAI accepts reports from any organisation, whether or not it is a member, and does not publish the identity of the reporting company. You can send an internal failure report or a third-party test report with supplier and customer details removed.
Sources: ERAI 2025 Annual Report; ERAI summary of the SAE AS6171 standard and slash sheets. ERAI figures are self-reported and are not independently verified.
