Is Emulation Legal in the UK? What the Law Says About ROMs and BIOS Files

The short answer: emulators are generally legal, copyrighted files are the difficult part

In the United Kingdom, using an emulator is not automatically illegal. An emulator is software that reproduces the behaviour of another computer, console or operating system. The law does not normally prohibit the general idea of creating software that performs this function. The legal position changes when copyrighted games, system software or firmware are copied, downloaded, shared or modified without permission.

For most people, the important distinction is this: the emulator and the game files are separate legal questions. A legally developed emulator can be used with files that the user has the right to possess and use. That does not make every ROM or BIOS file lawful. Equally, owning an original cartridge, disc or console does not automatically give a person unrestricted permission to download a matching digital copy from the internet.

The main UK legislation is the Copyright, Designs and Patents Act 1988, usually abbreviated to CDPA. It protects computer programs and other creative works, including many video games, graphics, music, dialogue, manuals and firmware. Copyright can apply to different elements of the same game, so a single ROM may contain several protected works.

What UK copyright law protects in a video game

The CDPA treats a computer program as a literary work for copyright purposes. The protection can cover the program code stored on a cartridge, disc, hard drive or other medium. A game may also contain separate artistic, musical and audiovisual works. Copying a game ROM can therefore involve reproducing more than just a small piece of software.

Copyright normally gives the rights holder control over acts such as copying the work, issuing copies to the public, renting or lending copies in some circumstances, communicating the work to the public, and adapting the program. The precise rights depend on the material involved, but the practical consequence is clear: copying a commercial game into a ROM file is not automatically permitted merely because the game is old, no longer sold or difficult to find.

UK law does not create a broad “abandonware” exception. A game that is no longer commercially available can still be protected. Age, rarity, a discontinued console or the absence of an active publisher do not by themselves remove copyright. The rights holder may be difficult to identify, but uncertainty about ownership is not the same as permission.

Is downloading or sharing ROMs legal in the UK?

Downloading a ROM from an unauthorised source will usually involve making a copy of copyrighted software. If the person supplying the file did not have permission, the download can raise copyright infringement issues even where the recipient owns the original game. Sharing ROMs is more clearly risky because uploading, hosting, emailing or distributing a file can involve copying and making it available to the public.

A few common arguments do not create a general legal defence:

• “I own the cartridge.” Ownership of a physical object does not normally transfer copyright in the game stored on it.
• “I am only using the ROM privately.” UK law does not provide a general private-use exception for copying commercial games.
• “The game is no longer sold.” Commercial unavailability does not automatically end copyright.
• “The download is free.” No payment does not mean that copying or distribution is authorised.
• “Everyone uses the same archive.” Widespread availability does not turn an unauthorised copy into a lawful one.

The person who uploads or distributes a ROM may face greater exposure than someone who downloads one, because distribution and public communication create additional legal issues. However, lower practical enforcement against an individual should not be confused with a legal permission to download.

What about making a ROM from a game you own?

This is one of the most misunderstood areas. A person may reasonably want to preserve a game they purchased and play it on modern hardware. That practical purpose does not necessarily mean that UK law permits every method of creating a digital copy.

Section 50A of the CDPA provides a specific exception for a lawful user of a computer program to make a backup copy when it is necessary for the lawful use of the program. This provision is narrower than a general right to copy any game for convenience. Whether a particular cartridge dump, disc image or extraction process falls within the provision can depend on the facts, the type of work and the purpose of the copy.

Several points matter:

• The person should be a lawful user, not someone who obtained the software through an unauthorised source.
• The copy should be genuinely connected with lawful use or backup, rather than being made for distribution or a public archive.
• Making a personal copy does not authorise sharing it with friends, uploading it or selling it.
• Owning a copy of a game does not necessarily provide permission to copy separately protected manuals, artwork, music or firmware.

The safest description is therefore not “owning the original makes ROM dumping legal”. The more accurate position is that UK law contains a limited computer-program backup exception, while the application to particular games and extraction methods may require specialist legal advice.

Are BIOS files legal to use with an emulator?

A BIOS file is system software used by some emulators to reproduce the start-up or hardware environment of a console or computer. It is not the same thing as the emulator. BIOS files are often copyrighted software, firmware or another protected form of code supplied by the original manufacturer.

Downloading a BIOS file from an unauthorised archive can therefore create the same basic problem as downloading a ROM. The fact that the file is small, old, required by an emulator or difficult to obtain does not remove copyright protection. A BIOS may also be subject to licence terms, technical protection measures or restrictions attached to the original hardware software.

A stronger legal and practical approach is to obtain the required system file from hardware that the user lawfully possesses, using a method that does not involve downloading someone else’s copy. Even then, the result should be treated as a private file. It should not be posted in an emulator package, attached to a forum message, placed in cloud storage for public access or distributed with game images.

Not every emulator needs a manufacturer BIOS. Some projects create replacement firmware through independent code, clean-room development or reverse engineering. That does not automatically make every replacement lawful, but it can avoid distributing the original copyrighted file. The legality depends on how the replacement was created and used.

Can an emulator include ROMs or BIOS files in its download package?

Including copyrighted game images or original BIOS files in an emulator package is a significant legal risk unless the distributor has permission or a clear legal basis. The emulator itself may be open source or freely downloadable, but that licence normally covers the emulator code, not third-party games and firmware.

Users should check what an installation package actually contains. A lawful-looking download may still bundle:

• commercial game ROMs used as demonstrations;
• original console BIOS files;
• copied artwork, manuals or music;
• keys or firmware extracted from a proprietary system;
• third-party components with separate licence conditions.

A project can also infringe through distribution even if it does not charge money. Copyright law is concerned with unauthorised acts, not only commercial sales. By contrast, homebrew games, public-domain software and works released under a licence that permits copying can generally be used according to their specific terms. “Free to download” and “free to copy” are not always identical, so the licence should be read rather than assumed.

Does UK law allow format shifting or private copying?

The UK once introduced a narrow private-copying exception, but that exception was quashed by the High Court in 2015 after a legal challenge. The result is important for retro gaming: there is no broad UK rule saying that a person may copy any music, film, game or software they own solely for personal convenience.

The position is different from the limited rules that apply to lawful computer-program users. Section 50A concerns a necessary backup copy of a computer program, not a general entitlement to digitise an entire personal collection. It should not be treated as a blanket answer for every cartridge dump or disc image.

There are also specific exceptions for activities such as research, criticism, review, quotation, education and text or data analysis, subject to conditions. Those exceptions do not normally provide a simple route for playing commercial ROMs at home. For example, copying a game to examine its code for a legitimate technical purpose is a different activity from downloading a complete commercial ROM to play it.

What are the rules on reverse engineering and interoperability?

The CDPA contains limited provisions concerning lawful users of computer programs. Sections 50B and 50BA address certain forms of decompilation, observation, study and testing. These provisions can be relevant when someone is investigating how software works or seeking the information needed for interoperability.

They are not a general permission to copy and distribute a game. A person cannot rely on reverse-engineering concepts simply because they want to obtain a playable ROM or reproduce a console library. The purpose, method and handling of the resulting material matter. Contract terms may also affect what a lawful user is allowed to do, particularly where software is supplied under a licence rather than sold outright.

Technical protection measures create another layer of risk. The CDPA includes rules concerning the circumvention of technological measures. Circumventing encryption, access controls or other protections to extract software may raise separate legal questions, even where the person owns the original device. Anyone working on preservation, compatibility or research at a serious level should obtain advice based on the specific hardware, software and intended publication.

A practical risk guide for UK players and preservation projects

The following table is a useful starting point, not a substitute for legal advice:

Activity	General UK position	Practical caution
Writing or installing an emulator	Generally lawful in itself	Check the emulator licence and avoid bundled copyrighted files.
Playing homebrew or public-domain software	Usually permitted under the applicable licence	Follow any conditions on copying, attribution or redistribution.
Downloading a commercial ROM from an unauthorised archive	Likely to involve unauthorised copying	Ownership of the original game does not automatically cure the issue.
Downloading an original BIOS file	Potential copyright infringement	Prefer a lawful dump from hardware you possess, and keep it private.
Uploading ROMs or BIOS files	High legal risk	Distribution and public availability can create additional infringement.
Making a backup copy of software	Potentially covered in limited circumstances by section 50A CDPA	Do not assume this permits public sharing or every form of ROM dumping.
Preserving a discontinued game	No automatic “abandonware” exception	Consider permissions, institutional arrangements and the status of each work.

For everyday use, a cautious setup is to use a reputable emulator without bundled commercial files, obtain homebrew or openly licensed software from an authorised source, and keep any personally created system files private. Avoid services that advertise large collections of commercial ROMs or BIOS files without identifying permission from the rights holders.

What preservationists, researchers and hobby developers should document

Legal and ethical questions become more manageable when the project is clearly defined. A person or group working on preservation should record:

1. Which hardware, software or game is being studied.
2. Who owns or controls the relevant copyright, if that information can be established.
3. How each digital copy was acquired and whether permission was granted.
4. Whether the copy is being used for private study, research, testing, access or distribution.
5. Which files contain original copyrighted material and which were independently created.
6. What technical protection measures were encountered and how they were handled.
7. Whether the final project will be available only to authorised users or to the public.

This record does not turn an infringing act into a lawful one, but it helps distinguish a carefully scoped preservation or compatibility project from an online ROM distribution service. It also makes it easier to seek informed advice from a UK intellectual-property solicitor, rights holder or relevant cultural institution.

Common questions about emulation, ROMs and BIOS files in the UK

Is using an emulator itself illegal?

Usually not. An emulator is generally a software tool, and its lawful status is separate from the status of the ROM, BIOS or other files used with it. The emulator licence and the way it was developed still matter.

Can I download a ROM if I own the physical game?

Ownership of the physical game does not automatically authorise downloading an unauthorised digital copy. A limited backup exception exists for lawful users of computer programs under section 50A of the CDPA, but it is not a general private-copying right and should not be treated as permission to download or share ROMs.

Can I share a BIOS file with another player?

Sharing an original BIOS file can involve distributing copyrighted software. The safer approach is not to share it and to obtain any required system software through a lawful method connected with hardware the user possesses.

Does “abandonware” make an old game legal to download?

No. UK copyright does not provide a general abandonware exception. A game can remain protected even when it is no longer sold, supported or easy to obtain.

What is the safest way to use emulation legally?

Use an emulator whose licence permits your intended use, choose homebrew or clearly licensed software, avoid unauthorised ROM and BIOS archives, and keep personally created backup files private. For distribution, preservation or reverse-engineering projects, obtain advice on the particular material and purpose.