What EU Regulation 655/2013 Requires Before You Print 'Clinically Proven' on Your Cosmetic Label

Three words on a serum box — clinically proven formula — represent a legal commitment most brands haven’t fully worked through. Under Implementing Regulation (EU) No 655/2013, that phrase requires documented evidence of a clinical test conducted on your finished product, run under conditions that reflect normal or reasonably foreseeable use, and reviewed by someone with appropriate scientific expertise. Marketing convention isn’t a defence.

The regulation came into force in 2013 and became fully applicable on 11 November 2015. That’s over a decade. And yet claims substantiation remains one of the most consistently under-resourced compliance functions in European cosmetics businesses — particularly for small and mid-sized brands that have invested heavily in formulation and branding but treat the claims dossier as an afterthought. It’s the kind of gap that stays invisible until an inspector asks to see it.

The Six Common Criteria — and What They Actually Demand

Regulation 655/2013 establishes six common criteria that every cosmetic claim must satisfy, regardless of where it appears: on the label, in a television ad, in a social post, or in an in-store display. The criteria are set out in the Annex to the regulation and elaborated in the European Commission’s Technical Document on Cosmetic Claims. They are: legal compliance, truthfulness, evidential support, honesty, fairness, and informed decision-making.

Most brands understand legal compliance in a rough sense — a claim can’t imply the product does something only a medicinal product can do. But the others are less intuitive than they look.

Truthfulness means the claimed effect must exist in your product. If your formula contains an active ingredient at 0.5% and the only available efficacy data was generated at 2%, citing that study doesn’t demonstrate truthfulness for your formulation. The evidence must relate to the product as sold, not to an ingredient’s theoretical potential.

Evidential support is where most dossiers collapse. The claim must be backed by adequate and verifiable evidence. The Technical Document is deliberately non-prescriptive about study design — it doesn’t mandate randomised controlled trials for every claim. But it does specify which evidence types are appropriate for which claim categories. Instrumental measurements for objective physiological effects. Consumer perception data for sensory or hedonic benefits. In vitro or ex vivo data for mechanistic support. Choosing the wrong evidence type for the specific claim you’re making is one of the most common gaps we identify when reviewing client dossiers.

Honesty goes further than truthfulness — it addresses selective use of data. If three studies tested your serum and two showed no significant effect on fine lines while one showed modest improvement, citing only the positive study violates this criterion, even if every statement you make about that study is technically accurate.

Informed decision-making catches vague claims that are technically defensible word-by-word but collectively misleading. A moisturiser described as “scientifically advanced with proprietary biotechnology” may not say anything false, but if it creates an impression of clinically validated performance that the product doesn’t have, the criterion is breached.

The Three Claim Types That Draw the Most Scrutiny

Not all claims carry equal enforcement risk. Based on patterns in DGCCRF market surveillance and the Commission’s Technical Document guidance, three categories generate compliance failures with notable frequency.

“Natural,” “clean,” and “organic” claims

These carry the highest risk in the current enforcement environment — partly because they’re popular, and partly because they have no statutory definition under EU Cosmetics Regulation (EC) No 1223/2009. There is no minimum percentage of plant-derived content required before a product can legally be called “natural.” There is no EU regulation specifying what “clean beauty” means.

That absence of a legal definition doesn’t protect you. In France, the DGCCRF has authority to pursue misleading claims under the Code de la Consommation governing unfair commercial practices — regardless of whether a specific provision of cosmetics regulation has been violated. If your product contains synthetic preservatives, petrochemical-derived emollients, or a fragrance blend that includes synthetic musks, and your packaging says “100% natural,” you have a substantiation problem under the truthfulness and honesty criteria.

Certification schemes like COSMOS — managed jointly by ECOCERT, BDIH, Cosmebio, Soil Association, and ICEA — fill part of the definition vacuum, but only if you’ve actually gone through certification. Using COSMOS-aligned language without certification is itself a fairness issue under the common criteria.

Duration-specific efficacy claims

“Moisturises for 24 hours.” “Visibly reduces fine lines in 4 weeks.” Each of these commits you to a specific, measurable timeframe. Substantiation requires instrumental measurements taken at the stated intervals. For a 24-hour hydration claim, the standard study design runs corneometry measurements — which measure skin capacitance as a hydration proxy — at baseline (T0), then at T4h, T8h, T12h, and T24h, against a vehicle control or untreated site.

A consumer questionnaire asking whether participants “feel more moisturised” isn’t adequate substantiation for a duration claim. The Technical Document is explicit: instrumental data is the appropriate evidence type for objective physiological effects, and consumer self-assessment is insufficient when the claim implies a measurable biological outcome at a specific timepoint.

“Dermatologist-tested” and expert-endorsement claims

These are legally permissible, but they require that the test was actually conducted by a qualified dermatologist — or directly supervised by one — on the finished product as sold, on a representative panel, under conditions that reflect real-world use. A dermatologist reviewing your safety assessment and confirming they see no contraindications is not a “dermatologist-tested” basis. That’s a safety review. It does not constitute efficacy testing, and conflating the two in your dossier is precisely the kind of misleading presentation the honesty criterion exists to prevent.

What “Evidential Support” Requires in Practice

The Technical Document groups acceptable evidence into four broad categories, and which one applies depends entirely on what you’re claiming.

Consumer perception studies are appropriate for sensory, aesthetic, or subjective benefit claims: pleasant texture, fast absorption, skin feeling softer. For these, panel size and study design matter. Studies should be statistically powered, conducted on the target population (not staff), and not prompted in ways that bias responses toward positive assessment.

Instrumental measurements are required for objective physiological claims — hydration, barrier function (measured via transepidermal water loss, or TEWL), sebum content, skin colour uniformity. The relevant ISO standards for these measurements exist precisely because regulatory authorities expect them to be followed.

In vitro and ex vivo data can support mechanistic claims about how an ingredient works — useful for claims like “stimulates collagen synthesis” — but the Commission is clear that in vitro data alone is insufficient to support a final product performance claim. It can contribute to the evidence package but can’t substitute for in vivo or clinical data.

Clinical studies are necessary for any claim implying medical-level efficacy — and here, “clinical” means a properly designed, ethically approved, human-subjects study. Borrowing clinical data from an ingredient supplier’s research dossier is only valid if the active is present in your formula at the same concentration, in the same delivery system, in the same matrix, tested in the same population.

One procedural point that surprises brands: all evidence must be available in your Product Information File (PIF) under Article 11(2)(c) of Regulation 1223/2009. The claims substantiation file isn’t a separate document you hold in case of trouble — it’s a mandatory component of the PIF. If your PIF doesn’t contain the substantiation file at the time of an inspection, the claims are presumed unsubstantiated.

How the DGCCRF Actually Approaches a Claims Investigation

France is a useful case study because the DGCCRF is among the more systematic market surveillance authorities for cosmetics in the EU. Their inspectors typically cross-reference three things simultaneously: the marketing materials (packaging, website, social channels, point-of-sale), the INCI list and concentration data, and the claims substantiation file.

If a claim on your packaging can’t be matched to a document in your dossier during an inspection, the default regulatory assumption is that no substantiation exists. The process then moves to a formal request — a mise en demeure — for documentation, followed potentially by administrative action: compelled reformulation or relabelling, fines, or referral to the procureur de la République in serious cases.

What makes this uncomfortable for brands is that enforcement doesn’t require proof of consumer harm. An unsubstantiated claim is a violation in itself — independent of whether any consumer was actually misled or suffered any negative consequence. The DGCCRF’s annual cosmetics sector surveys consistently rank misleading and unsubstantiated claims among their top documented violations across all product categories.

The Cross-Border Complication

EU claims standards don’t migrate cleanly to other markets, and European brands expanding to North America often discover this at an inconvenient moment. A “clinically proven” claim substantiated under EU criteria — perhaps a well-designed but modest-scale consumer perception study plus corneometry data — may not satisfy the US Federal Trade Commission’s standard of “competent and reliable scientific evidence,” which is typically interpreted by FTC enforcement as requiring adequately powered, controlled trials with objective endpoints.

Health Canada’s approach to cosmetic advertising in Canada sits on different statutory ground altogether, governed by the Consumer Packaging and Labelling Act and the Competition Act rather than cosmetics-specific regulation. Additionally, Health Canada’s Cosmetic Ingredient Hotlist restricts some ingredients permitted under Annex III of Regulation (EC) No 1223/2009 — making a claims dossier irrelevant if the ingredient itself can’t lawfully appear in the Canadian formula.

For European brands building their first claims package for an international launch, the practical approach is to design underlying studies with multi-market applicability in mind from the start. Define endpoints that satisfy the most demanding standard you’ll face. Pre-read the Technical Document requirements before commissioning external testing — not after, when changing a study design costs you another six months.

Building a Claims Substantiation Dossier That Holds Up

The dossier isn’t a single document. Think of it as a structured file with four components that need to stay current.

First, a claims matrix: a list of every claim in every format — on-pack, digital, in-store — with a reference to the corresponding evidence document. If a claim doesn’t have a corresponding evidence reference, it shouldn’t be on the packaging.

Second, the evidence itself: full study reports, not summaries. Statistical outputs, raw data if applicable, ethical approvals where required, test conditions, panel demographics, and a clear statement of which claim each study supports.

Third, a qualification summary: the credentials of whoever conducted or supervised the testing, and confirmation that they’re appropriate for the claim type. A cosmetic chemist may be appropriate for a formulation stability claim; a board-certified dermatologist is appropriate for a skin benefit claim.

Fourth, a version history: when each claim was reviewed, by whom, and in what role. This matters because reformulation resets the clock. Any change to the formula — including excipient changes, concentration adjustments, or supplier switches for an ingredient — requires review of whether existing evidence still supports the claims. Carrying over substantiation from a previous formulation without documented review is a fairness issue under the six common criteria.

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Pull one on-pack claim from your highest-volume product right now. Find the document in your PIF that substantiates it. If you can’t locate it within two minutes, you already know where your next audit vulnerability is — and fixing it before an inspector finds it is considerably less expensive than explaining it afterward.

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Written by Nour Abochama, Quality & Regulatory Advisor, Care Europe | VP Operations, Qalitex. Learn more about our team

Talk to our team about EU market entry — and how to build a claims dossier that holds up to DGCCRF scrutiny. Contact us

Related from our network

• ISO 17025-Accredited Cosmetic Testing at Qalitex Laboratories — US-based testing for efficacy, safety, and label claims substantiation to ISO 17025 standards, supporting European brands entering North American markets.
• Cosmetic and NHP Testing for the Canadian Market at Androxa — Health Canada-compliant testing services for European cosmetics and supplement brands seeking Canadian market entry.