The Framework of International Classification Treaties for Intellectual Property

When an inventor in Mumbai files a patent, or a fashion brand in Delhi registers its logo, or a design studio in Bengaluru seeks protection for a product’s look – they are all plugging into the same global IP infrastructure. But here’s a question worth pausing on: how do patent offices across 150+ countries understand and organise millions of IP filings consistently? The answer lies in a set of international classification treaties administered by the World Intellectual Property Organization (WIPO). These treaties don’t grant IP rights directly – they create the shared language and organisational systems that make searching, filing, and enforcing those rights possible across borders.

What are classification treaties and why do they matter? 🔗

WIPO administers three broad categories of treaties: protection treaties (which establish substantive rights), registration treaties (which enable international filings), and classification treaties. This last category is often overlooked in introductory IP courses, yet it forms the backbone of how IP offices worldwide process and retrieve information. As WIPO’s treaty framework describes it, classification treaties create systems that organise information about inventions, trademarks, and industrial designs into indexed, manageable structures for easy retrieval.

Without standardised classification, a trademark examiner in Chennai and one in Berlin would have no common framework to determine whether a similar mark had already been registered elsewhere. A patent examiner searching for “prior art” – existing technology that could block a new patent – would be navigating an incomparably fragmented database. Classification treaties solve exactly this problem by establishing common numerical and alphabetical codes that IP offices use universally, making the entire global IP system more coherent and searchable.

There are four primary classification treaties to understand: the Nice Agreement, the Locarno Agreement, the Strasbourg Agreement, and the Vienna Agreement. Each targets a different category of intellectual property.

The Nice Agreement (1957): classifying goods and services for trademarks 🔗

The Nice Agreement Concerning the International Classification of Goods and Services for the Purposes of the Registration of Marks was concluded in 1957 in Nice, France. It establishes what is commonly called the Nice Classification (NCL) – a standardised system that divides all goods and services into numbered classes for the purpose of trademark registration.

The classification comprises 45 classes in total: 34 classes covering goods (such as pharmaceuticals, clothing, electronics) and 11 classes covering services (such as advertising, banking, legal services). Each class contains an alphabetical list of specific goods or services, with the full list containing approximately 11,000 items. When a business applies to register a trademark – say, for a brand of packaged food – it must identify which Nice class or classes the goods fall under. This class number is then recorded in the official registration, making it searchable across member states.

The practical importance of this is significant. According to WIPO, trademark offices of all contracting states are obligated to indicate in official documents and publications the class numbers corresponding to each registered mark. This means that a search on WIPO’s Global Brand Database, or on India’s own trademark registry, uses Nice Classification codes to return results – enabling brand owners and examiners to check for conflicting marks efficiently.

India acceded to the Nice Agreement on 7 September 2019, becoming its 88th member. Before this, Indian trademark filings already used the Nice Classification informally – the accession formalised this alignment with the international standard. The Nice Classification is continuously revised by a Committee of Experts drawn from member states, with new editions periodically incorporating new product categories and service types as industries evolve.

The Locarno Agreement (1968): classifying industrial designs 🔗

The Locarno Agreement Establishing an International Classification for Industrial Designs was concluded in 1968. It creates the Locarno Classification (LOC), which is used specifically for the registration of industrial designs – the ornamental or aesthetic aspects of a product, such as the shape, pattern, or colour of a chair, a smartphone, or a textile print.

The Locarno Classification organises products into 32 classes and 219 subclasses, accompanied by an alphabetical list of approximately 7,000 goods that indicates which class each product type falls into. So, for example, clothing falls into one class, furniture into another, and packaging containers into yet another. When an IP office registers a design, it records the Locarno class and subclass of the goods incorporating that design. This makes it far simpler for designers and examiners to search for prior registrations of similar designs across different product categories.

India also acceded to the Locarno Agreement on 7 September 2019, alongside the Nice and Vienna Agreements. For India’s design ecosystem – which includes industries from automotive and consumer electronics to handloom and handicrafts – this was an important administrative alignment. Intellectual property offices of member states are required to indicate the Locarno class and subclass in official documents relating to the deposit or registration of industrial designs. Like all WIPO classification systems, the Locarno Classification is periodically revised by its Committee of Experts to keep pace with new product types.

The Strasbourg Agreement (1971): the international patent classification 🔗

For patents, the relevant classification framework comes from the Strasbourg Agreement Concerning the International Patent Classification, concluded in 1971. This agreement establishes the International Patent Classification (IPC), which is the most extensively used of all four classification systems given the sheer volume of patent filings globally.

The IPC divides all areas of technology into eight broad sections, which are then further broken down into approximately 80,000 subdivisions. Each subdivision is represented by a symbol made up of Arabic numerals and letters of the Latin alphabet – for instance, the class “A61K” refers to preparations for medical, dental, or toilet purposes. These symbols are printed on every published patent application and granted patent. The IPC is indispensable for searching “prior art” – the body of existing technology that patent examiners review to determine whether a new invention is genuinely novel.

The system is used not just by contracting states. The patent offices of more than 100 states, four regional IP offices, and the WIPO Secretariat administering the Patent Cooperation Treaty all use the IPC framework. For PCT applications – the international patent filing system – IPC symbols are allotted by the International Searching Authority handling the application. India, while not a party to the Strasbourg Agreement itself, uses the IPC in practice through its engagement with the PCT system.

The IPC is revised regularly by the IPC Committee of Experts under the Strasbourg Agreement. Revisions are necessary because technology moves fast – new fields such as artificial intelligence, blockchain, and gene editing require new classification categories to remain searchable within the global patent database.

The Vienna Agreement (1973): classifying figurative elements of marks 🔗

The fourth classification treaty is the Vienna Agreement Establishing an International Classification of the Figurative Elements of Marks, concluded in 1973. It establishes the Vienna Classification (VCL), which is used to classify the visual or figurative elements of trademarks – that is, logos, images, and design features that form part of a mark.

This is a distinct function from the Nice Classification. Nice tells you what goods or services a mark covers. Vienna tells you what the mark actually looks like. The Vienna Classification organises figurative elements into a hierarchical system of categories, divisions, and sections – for example, categories for human figures, animals, natural phenomena, geometric shapes, text in particular scripts, and so on. IP offices record Vienna Classification codes in official publications relating to marks that contain figurative elements.

This classification is particularly useful for trademark searches. When a business wants to register a logo featuring, say, a stylised lion, examiners can search the Vienna Classification to find all registered marks in the relevant territory that contain similar figurative elements. This makes conflicts easier to identify and assess. India became the 34th member of the Vienna Agreement when it acceded in September 2019.

How these four systems work together 🔗

It is worth understanding these four classification systems not as isolated instruments but as a coordinated framework. A single trademark registration, for instance, may draw on two of them simultaneously: the Nice Classification to identify the goods or services the mark covers, and the Vienna Classification to categorise the figurative elements of the logo. A registered industrial design uses the Locarno Classification. A patent uses the IPC under the Strasbourg Agreement.

Together, they enable the global IP system to function as a searchable, cross-border database. When India’s Intellectual Property India examines a new trademark application, it uses Nice and Vienna codes to check for conflicting prior registrations – not just in India, but as a reference against international databases. When WIPO publishes international trademark registrations through its Madrid System, those registrations carry Nice and Vienna codes, making them retrievable globally.

This interoperability has direct consequences for IP holders. If you are a startup in Pune registering a brand name and logo across multiple countries, your legal counsel will rely on Nice Classification codes to determine which product categories need to be covered in each jurisdiction, and Vienna codes to search for visually similar marks. A pharmaceutical company filing a patent for a new drug compound will rely on IPC codes to conduct a prior art search across PATENTSCOPE, WIPO’s global patent database, which holds millions of patent documents indexed by IPC symbols.

India’s engagement with classification treaties 🔗

India’s 2019 accession to the Nice, Locarno, and Vienna Agreements was a significant step in aligning Indian IP administration with international standards. As WIPO Director General Francis Gurry noted at the time, India had been active in IP reform and international cooperation, with a marked improvement in its rankings on the Global Innovation Index. Formalising classification treaty membership reflected both India’s growing IP filing volumes and its intent to make the Indian IP system more compatible with global practice.

From an administrative standpoint, accession means Indian trademark and design registrations now carry internationally standardised class codes, making them more reliably searchable by foreign companies conducting clearance searches before entering the Indian market. It also means Indian businesses filing abroad can expect their domestic classification data to be consistent with what foreign offices expect – reducing delays and ambiguity in international filings. India’s non-membership of the Strasbourg Agreement remains a gap in this picture, though the practical use of IPC through the PCT partially compensates for this.

Why classification systems are not merely administrative tools 🔗

It is tempting to treat classification treaties as dry procedural instruments – bureaucratic plumbing beneath the more glamorous surface of patent grants and trademark rights. But their significance runs deeper. Classification systems determine how prior art is found, and whether it is found at all. A poorly classified patent may never surface in a prior art search, allowing a subsequent, duplicative patent to be granted. A trademark registered in the wrong Nice class may not be discovered by a conflict search, leading to costly disputes after launch.

For IP law students, understanding classification treaties is also about understanding the infrastructure of the global IP system. Every WIPO global database – PATENTSCOPE for patents, the Global Brand Database for trademarks, and the Global Design Database for industrial designs – is built on the classification systems established by these treaties. Knowing how to read and use IPC, Nice, Locarno, and Vienna codes is a practical skill that cuts across patent prosecution, trademark clearance, design registration, and IP litigation.

Classification treaties also have a quiet but real effect on innovation policy. When governments analyse patent filing trends to identify technology gaps or emerging sectors, they do so using IPC codes. When WIPO publishes its annual IP statistics, the data is structured by classification codes. The maps of innovation that inform both private investment and public policy are drawn using the frameworks these treaties established decades ago.

What do you think? Given that India has acceded to the Nice, Locarno, and Vienna Agreements but not the Strasbourg Agreement, does this create a meaningful gap in how Indian patent filings are handled internationally – or does India’s participation in the PCT sufficiently bridge this difference? And as new categories of IP-intensive goods emerge – think AI-generated works, biotechnology products, or digital fashion assets – how should classification systems evolve to stay relevant?

References

1. https://www.wipo.int/treaties/en/
2. https://www.wipo.int/en/web/classification-nice
3. https://www.wipo.int/portal/en/news/2019/article_0021.html
4. https://www.wipo.int/en/web/classification-locarno
5. https://www.wipo.int/en/web/treaties/classification/strasbourg/summary_strasbourg
6. https://www.khuranaandkhurana.com/2023/07/14/eminent-wipo-conventions-treaties-agreements/
7. https://www.wipo.int/en/web/classification-vienna
8. https://ipindia.gov.in/
9. https://www.wipo.int/patentscope/en/