In a recent Patents Court decision, Mrs Justice Bacon examined how patent protection and trade mark law intersect. The case of Banham Patent Locks Limited v Mr Rogers (trading as J Rogers & Sons) clarifies the limits of the "honest commercial practices" defence under section 11(2)(c) of the Trade Marks Act 1994, particularly when the advertised services involve patent infringement.

Case summary

Banham brought a claim for patent infringement and trade mark infringement against the defendant, Mr Rogers trading as J Rogers & Sons. In particular, Banham alleged that the defendant unlawfully cut patented keys and the advertisement of its services under the sign "BANHAMS COPIED" infringed Banham's trade mark.

Banham subsequently brought an application for judgment in default and/or strike out and/or summary judgment, heard by Mrs Justice Bacon. 

Background

Banham supplies premium lock and key products for domestic and commercial use and alleged patent infringement in respect of two patents: GB 2488783 and EP 2497882 (the 'Patents').The Patents cover keys referred to by Banham as its "Mark III" keys and preclude anyone from duplicating or cutting keys without Banham's express consent. However, any locksmith can cut earlier models of Banham's keys, such as its "Mark I" and "Mark II" keys, as the relevant patents have expired.

Banham also alleged trade mark infringement in relation to two word marks for BANHAM (UK0002301556A and UK00902968923) registered in Class 6 for "keys, parts and fittings for the aforesaid goods".

The defendant is a sole trader who operates a family-run shoe repair and key cutting business under the name "J Rogers & Sons", with four branches in London. 

The parties had previous dealings: in 2023, Banham discovered J Rogers & Sons had cut Mark III keys and sent Mr. Rogers a letter before claim. On 5 December 2024, Mr Rogers signed undertakings that he would stop making, disposing of, or offering to dispose of Mark III keys, would not infringe the Patents, and would destroy inventory used to make the infringing keys.

In May 2025 Banham sent investigators to two branches of J Rogers & Sons to attempt to obtain copies of the Mark III keys. Their report said staff readily cut copies of the Mark III keys and identified a poster advertising the cutting of Mark III keys. 

Patent infringement 

Claim 1 of both Patents requires that the key has a series of recess pairs aligned on the opposite main faces of the key. Mr Rogers referred to these in his correspondence as "dimples". Critically, the claims also describe that the Mark III key has two pairs of cut-outs, referred to as "notches", with each pair of notches aligned on opposite side edges of the key, and with the two pairs "axially spaced" (i.e., positioned at a distance from each other along the length of the key). The claims do not specify what that distance should be, so it may vary from key to key.

The difference between a Mark III key and the earlier Mark II key is that the Mark II has dimples but only a single pair of notches on the side edges, located just below the head of the key. Key blank suppliers readily make available blanks with that pair of notches pre-cut. There is no dispute that key cutters other than Banham can reproduce Mark II keys without infringing the Patents: all the key cutter needs to do is reproduce the dimples along the main surface of the key. The Mark III key, by contrast, has a second pair of notches along the shaft of the key. To cut a Mark III key, therefore, the cutter must reproduce both the dimples and this second pair of notches.

At the hearing, Mr Rogers represented himself and raised two points. First, he contended that the keys obtained by Banham's investigators were Mark II and not Mark III. Secondly, he claimed that the keys cut by his business were not and could not be infringing Mark III keys, because they were cut on what he referred to as "Mark II" key blanks which had only one pair of notches. The court was not persuaded on either front.

As to the second point, the court found this rested on a misunderstanding of Banham's claim. Banham did not claim that the use of any particular key blank was an infringement; rather, Banham alleged that cutting the relevant key blank into Mark III keys infringed the Patents. Since the claims do not specify a location for the second pair of notches on a Mark III key, that location will differ from key to key. A key cutter can therefore cut a Mark III key from exactly the same key blank used to produce a Mark II key, the difference being that for a Mark III key, the cutting process adds not only the required dimples but also the second pair of notches.

Mr Rogers abandoned his argument about Mark II key blanks and instead argued that his employees could not have cut Mark III keys because they had been trained not to do so. The court was not convinced that Mr Rogers would be able to provide evidence of this training at trial.

Breach of undertaking 

The court found Mr. Rogers breached his undertaking in relation to the patent infringement. In relation to a "blue poster" (as it was described by the court), Mr Rogers argued that this was a generic poster which did not specifically identify a Banham Mark III key. The court rejected that submission because the poster depicts a key with dimples and two pairs of notches, i.e. the hallmarks of a Mark III key as opposed to a Mark II key. In the result, the court found nothing in Mr Rogers' submissions that could provide any defence to the claim for breach of undertaking.

Trade mark infringement 

Banham alleged trade mark infringement on the basis that: (i) Mr Rogers purchased and sponsored adverts on Google that read "key cutting, all types of key cutting, including security, multi-lock, Banham, household, office keys and more"; and (ii) the Putney branch of J Rogers & Sons displayed the blue poster with the phrase "BANHAMS COPIED", and an image of what is alleged to be the Mark III key.

The court did not reach any finding as to the Google advert because there was some doubt whether this was, as pleaded, a sponsored advert or simply a reference to an old website. 

However, the court did review the blue poster and found that it contained a picture of a Banham Mark III key with two pairs of notches. Furthermore, around that image, in capital letters, was the phrase "BANHAMS COPIED". Banham assented that this is use of a sign either identical to, or highly similar to, its "BANHAM" marks, used for identical goods and services (i.e. the cutting of Banham keys) contrary to ss. 10(1) and/or 10(2)(b) of the Trade Marks Act 1994.

Mr Rogers argued that his shops are entitled to cut Banham Mark I and II keys without breaching the Patents and the blue poster was entitled to advertise that fact.

The court considered whether Mr Rogers could advance a defence of honest commercial use pursuant to s.11(2)(c) of the Trade Marks Act 1994, which provides that:

"A registered trade mark is not infringed by – ... (c) the use of the trade mark for the purpose of identifying or referring to goods or services as those of the proprietor of the trade mark, in particular where that use is necessary to indicate the intended purpose of a product or service (in particular, as accessories or spare parts), provided the use is in accordance with honest practices in industrial or commercial matters."

Banham argued that the defence could not apply in circumstances where the blue poster was being used to advertise a service that extended not only to the lawful copying of Mark I and II keys, but also (as the court found) to the unlawful copying of Mark III keys. In such circumstances, the use of Banham's word marks cannot be established as being "in accordance with honest commercial practices". The court agreed, finding that Mr Rogers could not rely on the defence of honest commercial practices where the advertisement in question promotes services that include patent infringement.

Comment

This decision is a useful reminder of the interplay between patent and trade mark rights. It demonstrates that a defendant may not be able to invoke the defence of honest commercial practices under s. 11(2)(c) of the Trade Marks Act 1994 where the use of a trade mark is connected to underlying unlawful activity, in this case, patent infringement.

For brand owners, the case highlights the value of robust enforcement strategies combining multiple IP rights. For traders, it underscores the importance of ensuring that any advertising which references third-party trade marks is limited to genuinely lawful services and a defence of honest practices will fail if the advertised services extend beyond what is legally permissible.