1. The lot number, above all else
A certificate without a lot number is just a pretty piece of paper. A lot number that doesn’t also appear on the product you’re holding is just a pretty piece of paper.
This is the most common—and simplest—form of fraud on the market: a seller has a good batch tested, then uses that same PDF for two years on everything they sell. Nothing is forged. The document is authentic. It simply no longer describes anything.
Also check for the phrase “sample provided by the customer.” It’s perfectly legal and appears on most reports, including ours. But it means that the lab guarantees the analysis, not the representativeness: it tested what was sent to it.
2. CBD, CBDA, and the 0.877 Factor
This is the most manipulated line on the market, and it stems from a multiplication factor that no one explains.
In the living plant, cannabidiol is present in its acidic form: CBDA. Heat—drying, pressing, combustion, vaporization—causes it to lose a CO₂ molecule and converts it into CBD. This is decarboxylation.
This lost CO₂ has a mass. CBDA weighs 358 g/mol, and CBD weighs 314 g/mol. The ratio is 0.877. The calculation is therefore: Total CBD = CBD + (CBDA × 0.877).
Let’s take a real resin sample: 3% CBD and 52% CBDA. A simple addition yields 55%. The correct calculation yields 48.6%.
A six-point difference. More than a 13% overestimation, without falsifying a single value on the certificate —all it takes is adding two lines that the lab took care to separate. When a product sheet lists a percentage significantly higher than that in the report, the answer is almost always right there.
3. Total THC: That Same 0.877 Determines Your Legal Status
The same rule applies to THC: total THC = THC + (THCA × 0.877). And here, it’s no longer a matter of marketing, but of compliance.
Many certificates list a “delta-9-THC” line with a reassuring value, and a “THCA” line below it that no one reads. Example: 0.05% delta-9-THC and 0.35% THCA result in a total THC of 0.357%.
This product is legal in Switzerland, where the threshold is 1%. It is not legal in France or in most of the European Union, where the limit is 0.3%—though Italy allows up to 0.6%.
A French retailer who looks only at the “delta-9” line believes they are importing a compliant product. It is not. And it is the stockholder who is liable for exceeding the limit, not the Swiss producer.
Always look for the explicit statement “total THC.” If it’s not listed, do the calculation yourself.
4. The Method: HPLC or GC
A technical detail, often in fine print, that changes how you interpret everything else.
HPLC, or high-performance liquid chromatography, operates at room temperature. It separates the acidic forms from the neutral forms and provides CBDA and CBD, THCA and THC, separately. This is what you need.
GC(gas chromatography) heats the sample upon injection. Decarboxylation occurs within the instrument: the acidic forms disappear and are counted along with the neutral forms. The result is already a total, but you can no longer tell which came from where.
A GC report is neither false nor fraudulent. But if you apply the 0.877 factor to it, thinking you’re correcting a number, you’re underestimating the product. And a certificate that doesn’t specify its method is uninterpretable—that in itself is a red flag.
5. LOD and LOQ: “Not detected” does not mean zero
The LOD is the limit of detection: below this level, the instrument detects nothing. The LOQ is the limit of quantification: the molecule is present, the laboratory detects it, but cannot provide a reliable figure.
Hence the notation “< LOQ” or “n.d.” It does not mean “absent.” It means present in an amount too small to be quantified by this method.
These thresholds vary from one laboratory to another, typically ranging from 0.01% to 0.05% for cannabinoids. Direct consequence: a claim of “0% THC” makes no sense if the LOQ is not specified. Two identical products may be labeled “not detected” for one and “0.02%” for the other.
6. The total never adds up to 100%—and that’s normal
A trichome head is not a pure crystal. It contains cannabinoids and terpenes, but also lipids, waxes, water, and plant fragments. This is what gives it its texture, color, and behavior when pressed.
A well-executed dry sift using a 153-micron mesh yields a resin whose total cannabinoid content remains consistent with this biological reality. Beyond a certain threshold, the issue is no longer the quality of the sifting: something has been added. Crystallized isolate, distillate, synthetic terpenes.
An abnormally high total cannabinoid content in a resin is a red flag, not a selling point.
7. Wet or dry weight: what does the percentage refer to?
The same sample yields two different results depending on the basis of calculation. On a raw basis —“as received”—the percentage refers to the product as is, including moisture. On a dry weight basis —“dry weight”—water is excluded from the calculation.
For a flower with 10% moisture content, the difference between the two bases is approximately 10% across all values. That’s enough to push a batch just over or just under a regulatory threshold.
European regulations are based on dry weight. Many product data sheets, however, choose whichever basis suits them best. Check which one is specified before comparing two products.
8. What the Certificate Doesn’t Say
This is the most important—and most misunderstood—point: a lab only finds what it’s looking for.
A standard cannabinoid profile covers a fixed list of molecules—often eight, sometimes sixteen. Anything not on that list is invisible, even in large quantities. Semi-synthetic molecules and compounds from the synthetic family do not appear in any standard panel: they slip through without leaving a trace on the report.
Also absent, unless specifically requested and billed separately, are: pesticides, heavy metals —the plant is a hyperaccumulator, so this is not just a theoretical point—, microbiology, mycotoxins, residual solvents, and the terpene profile, which requires a separate GC-MS analysis.
“Laboratory-analyzed” therefore means nothing on its own. The relevant question is: analyzed for what?
