Regulatory Compliance

Supporting materials for claims about effects and performance, and rules on unsubstantiated advertising

For representations promoting the effects or performance of goods or services, the Consumer Affairs Agency (CAA) and prefectural governors may request the submission of materials showing reasonable grounds for the representations under the Act against Unjustifiable Premiums and Misleading Representations (the "Premiums and Representations Act"). It is important to assess, in relation to the advertisement, whether the test results, literature, and manufacturers' materials held by a company support the wording of that advertisement.

The guidelines on unsubstantiated advertising set out two criteria for determining whether materials show reasonable grounds: the materials must contain objectively substantiated information, and the claimed effects or performance must correspond appropriately to what the materials demonstrate. The existence of test results alone does not necessarily substantiate the wording of an advertisement.

We assist with checking the correspondence between advertisements and supporting materials, identifying gaps in the materials and issues affecting their assessment, and preparing for requests to submit materials.

Reviewed by Keishi Yoshikawa, Attorney at Law and Patent Attorney (Dai-Ichi Tokyo Bar Association)

Last updated: September 27, 2026

What to check first

The following are examples of matters a company may wish to check when reviewing claims about effects and performance.

The representation as a whole — The company identifies the full content of advertisements planned for publication or already published, including text, images, videos, testimonials, and notes.
Claims requiring substantiation — The company breaks down claims about effects and performance by intended users, conditions of use, the extent of the effects, the time until the effects appear, and similar factors.
Materials corresponding to each claim — The company checks whether test reports, literature, and manufacturers' materials corresponding to each claim are available, and when they were obtained or prepared.
Details of the tests — The company checks the testing methods, sample size, controls used for comparison, measurement items, methods of aggregating the data, and variability in the results.
The tested item and the product sold — The company checks for differences between the tested item and the product sold, including model numbers, specifications, ingredients, ingredient quantities, and methods of use.
Test conditions and the situation depicted in the advertisement — The company checks whether the test conditions correspond to the environment, intended users, and duration of use suggested by the advertisement.
Obtaining materials and identifying contacts — The company checks whether the full materials and accompanying documents can be obtained, and whether the relevant contacts at the manufacturer or testing institution are known.
Requests already received — If the company has received a request to submit materials or a disclosure request, it separately identifies the sender, the legal provision on which the request is based, the representation concerned, and the deadline.

Because the time available for preparation after a request to submit materials is limited, the company may consider completing these checks before making the representation.

How we can helpChecking the correspondence between representations and materials / Assessing testing and survey methods / Identifying gaps in materials / Preparing for requests to submit materials / Checks with manufacturers and testing institutions

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Contents

1 What to substantiate, and with which materials
2 Do the materials contain objectively substantiated information?
3 Do the claimed effects and performance correspond to what has been demonstrated?
4 Preparing for a request to submit supporting materials
Key legislation and official sources
Frequently asked questions

1 What to substantiate, and with which materials

Identifying the effects and performance communicated by the advertisement

Before considering substantiation, the company identifies what the advertisement communicates to general consumers. Based on the representation as a whole—not only its wording, but also images, testimonials, and notes—the company sets out the claims by intended users, conditions of use, the extent of the effects, the time until the effects appear, and similar factors. How to assess what an advertisement communicates is explained in "Assessing advertising content: prominent claims and disclaimers."

Scope of the rules on unsubstantiated advertising and the submission deadline

The rules on unsubstantiated advertising apply to representations about the content of goods or services where the question is whether they constitute misleading representations as to quality under the Premiums and Representations Act. The Regulations for Enforcement of the Act against Unjustifiable Premiums and Misleading Representations (the "Enforcement Regulations") provide that the submission period ends on the day on which 15 days have elapsed from the date the written request is delivered, unless there are recognized justifiable grounds for not submitting the materials within that period. The guidelines on unsubstantiated advertising also state that the need to conduct new or additional tests or surveys is not recognized as justifiable grounds for extending the deadline. The company may therefore consider identifying, at the time it makes a representation, the materials that support it.

Organizing claims and corresponding materials

We recommend preparing, for each claim, a list that identifies the product concerned, the materials relied on for substantiation, the scope of what those materials demonstrate, and matters that have not been confirmed.

2 Do the materials contain objectively substantiated information?

Testing and survey methods

The guidelines on unsubstantiated advertising identify results obtained through tests or surveys, and opinions of experts, expert organizations, or specialized institutions, or academic literature, as objectively substantiated information. The guidelines state that tests and surveys must use methods generally accepted in the academic or industrial field relevant to the claimed effects or performance, or methods accepted by a majority of experts in the relevant field.

Sample size, comparison conditions, and methods of aggregating data

The sample size, conditions used as controls for comparison, and methods of measurement and data aggregation are assessed for their suitability in relation to the claimed effects. The guidelines state that, where generally accepted methods or other such methods do not exist, tests and surveys must use methods considered appropriate in light of commonly accepted social understanding and experience. The company checks not only the number of participants, but also whether participant selection, control conditions, evaluation criteria, and analytical methods correspond to the advertising claims.

Expert opinions, academic literature, and testimonials

The guidelines state that, when consumer testimonials or opinions of test users are used as substantiating materials, sufficient statistical objectivity must be secured, for example by selecting a substantial number of samples through random sampling and conducting the research with precautions against bias. In our view, simply collecting favorable testimonials does not produce objectively substantiated materials.

In-house tests and manufacturers' materials

The guidelines state that tests or surveys conducted by the business itself, including its affiliated institutions, may be submitted as grounds for a representation, provided that generally accepted methods or other such methods are used. They also state that a seller is not always required to conduct its own substantiation tests: it may instead submit documents showing that it has itself checked whether test data from the manufacturer or another relevant party exist, and the objectivity of the methods and results. Since a manufacturer's explanation that a product "is effective" is not necessarily sufficient, the company may consider checking the test reports, methods, and results and retaining a record of those checks.

3 Do the claimed effects and performance correspond to what has been demonstrated?

Differences between the tested item and the product sold

The guidelines on unsubstantiated advertising state that materials are not recognized as showing reasonable grounds unless the claimed effects or performance correspond appropriately to what the materials demonstrate. Where test results for raw materials, components, or prototypes are presented as the effects of a finished product, the implications of differences in ingredient quantities, structure, methods of use, and similar factors for what has been demonstrated are considered. For health foods, the CAA's points to note give examples of papers that did not demonstrate a product's effects, including papers containing only general statements about an ingredient and papers in which the participants' intake differed substantially from the amount contained in the product. In our view, whether test results for raw materials or components also substantiate the effects claimed for the finished product sold needs to be assessed case by case, taking account of ingredient quantities, structure, conditions of use, and similar factors.

Environment, intended users, and duration of use

The guidelines give examples such as a test demonstrating only temporary avoidance behavior inside an acrylic test case, which does not demonstrate practical pest control effects. The company checks whether laboratory conditions, participant characteristics, and the amount, frequency, and duration of use correspond to the actual situations envisaged by the advertisement. In our view, whether a short test also substantiates claimed effects during long-term use needs to be assessed case by case, considering the observation period, the onset and duration of the effects, and the conditions of use.

Measured indicators and the effects promoted

Whether a change in a particular measured value also substantiates the ultimate effect promoted in the advertisement is considered separately.

The extent to which numerical and comparative results can be generalized

The company identifies results obtained under particular conditions, averages, maximum values, and the subjects of comparison, and checks whether the claimed effects or their scope extend beyond what the materials support. For each claim, the company identifies which materials demonstrate what, and which aspects remain unsubstantiated. As an example of information sharing, the annex to the management measures guidelines describes the department responsible for changes to the content of goods or services promptly communicating information to the department responsible for representations when those changes may affect the representations. When specifications change, the company compares the changes with the conditions of the previous tests and distinguishes between aspects that can be explained by existing materials and those requiring additional checks.

4 Preparing for a request to submit supporting materials

"Deemed" for orders to take measures and "presumed" for surcharges

Under the Premiums and Representations Act, if materials showing reasonable grounds for a representation are not submitted within the specified period, the representation is deemed to be a misleading representation as to quality for the purposes of an order to take measures, and is presumed to be such a representation for the purposes of an order to pay a surcharge. Because "deemed" and "presumed" have different effects, the company checks which procedure forms the basis of the request to submit materials.

Materials and explanations for the company to organize

We assist with organizing lists of materials for each representation, test conditions, the scope and limitations of what has been demonstrated, and records of checks with manufacturers and testing institutions.

Disclosure requests from qualified consumer organizations

Under the Premiums and Representations Act, a qualified consumer organization may also request disclosure of materials showing reasonable grounds for a representation. This is a separate mechanism from an authority's request to submit materials, but it likewise concerns materials supporting a representation, and the assessment of their content is at issue. Responses to such requests and handling procedures before the authorities are explained in "Alleged violations of the Premiums and Representations Act, voluntary correction, and regulatory responses."

Review of the operation of the rules on unsubstantiated advertising

The government's Regulatory Reform Implementation Plan, adopted by Cabinet decision on July 21, 2026, provides that the CAA is to consider the following matters concerning the operation of the rules on unsubstantiated advertising, including amendments to the guidelines on unsubstantiated advertising, after seeking a broad range of views from businesses, general consumers, and others, and reach conclusions in fiscal year 2027. The first is for the CAA, both when requesting materials and during the preceding investigation, to explain to the business, in writing wherever possible, its view of the impressions and understanding that general consumers derive from the representation. The second is for the CAA, when issuing an order to take measures, to explain specifically why it found that the submitted materials did not show reasonable grounds, and to publish those reasons with due regard for trade secrets.

This page is based on the guidelines and their operation as of September 2026. If amendments to the guidelines or other changes are published, we will review their content and update this page.

Key legislation and official sources

English translations of legislation are provided for reference. The Japanese texts are authoritative.

Article topic	Legislation or official source	Source type and English version reviewed
Requests for materials; misleading representations as to quality; deemed and presumed treatment; disclosure requests from qualified consumer organizations	Act against Unjustifiable Premiums and Misleading Representations— Japanese text on e-Gov	Legislation. English translation (earlier version). The translation identifies its last version as Act No. 29 of 2023.
The 15-day submission period	Regulations for Enforcement of the Act against Unjustifiable Premiums and Misleading Representations— Japanese text on e-Gov	Cabinet Office Order. English translation (earlier version). The translation identifies its last version as Cabinet Office Order No. 54 of 2024.
The two requirements for reasonable grounds; testing methods; testimonials; in-house tests; manufacturers' data; extensions of the deadline	Guidelines on unsubstantiated advertising	Official guidance (Japanese). English translation on Japanese Law Translation; the page does not state the version translated.
Whether literature on ingredients substantiates the effects of health food products	Points to note under the Premiums and Representations Act and the Health Promotion Act concerning health foods	Official guidance (Japanese). English title translated by the firm.
Sharing information about changes to goods or services; retaining supporting materials	Management measures guidelines	Official guidance (Japanese). English title translated by the firm.
Planned review of the operation of the rules on unsubstantiated advertising	Regulatory Reform Implementation Plan, July 21, 2026	Cabinet decision (Japanese). English title translated by the firm.

Legal information reviewed: September 27, 2026

Frequently asked questions

Can test results be used as grounds only if the tests were conducted by a third-party institution?

The guidelines on unsubstantiated advertising state that tests or surveys conducted by the business itself or its affiliated institutions may be submitted as grounds, provided that generally accepted methods or other such methods are used. Even where tests were conducted by a third-party institution, their correspondence with the claimed effects or performance needs to be considered separately.

Is an explanation from the manufacturer that the product "is effective" sufficient?

The guidelines describe a method under which a seller may submit documents showing that it has itself checked the existence of the manufacturer's test data and the objectivity of the methods and results. Since receiving an explanation alone is not necessarily sufficient, the company may consider checking the reports and other materials and retaining a record of those checks.

Can a paper on an ingredient substantiate the effects of the product?

Academic literature can serve as objective substantiation, but the issue is whether the quantity of the ingredient, conditions of use, and evaluation criteria addressed in the paper correspond to the actual product and representation. Findings about an ingredient do not necessarily substantiate the effects of the finished product.

Can collecting testimonials or impressions from test users substantiate the effects?

The guidelines state that, when testimonials or opinions of test users are used as substantiating materials, sufficient statistical objectivity must be secured, for example by selecting a substantial number of samples through random sampling.

Can the deadline be extended to allow tests to be conducted after a request to submit materials is received?

The guidelines on unsubstantiated advertising state that the need to conduct new or additional tests or surveys is not recognized as justifiable grounds for extending the deadline.

Which materials can the company retain to support its representations?

The company may consider retaining test and survey reports showing the methods, subjects, conditions, and results; the full text of relevant literature; manufacturers' materials and records of checks of their content; and lists showing the correspondence between claims and supporting materials. The management measures guidelines also identify retaining materials as a measure enabling the information supporting representations to be checked subsequently.

Contact

Making an inquiry

Please let us know, as far as you are able, the proposed advertisement and the materials relied on to support it (such as test reports, literature, and manufacturers' materials) and, if you have received a request to submit materials, the request document and the deadline.