East Asia

This page is not legal advice. The law of the country where you live applies to you.

South Korea and China have written software exceptions. Japan has a general exception for uses that are not for enjoying the work. Taiwan and Hong Kong rely on fair use or fair dealing. In this region, rights holders and police have acted mostly against people who sell devices, services or edited game data.

Japan

• Studying a program. Japan has no decompilation article. Art. 30-4 of the Copyright Act, in force from 1 January 2019, permits uses that are not for enjoying the work, unless they unreasonably harm the owner (CRIC translation). Analysing code counts as a use that is not for enjoyment. Playing the game counts as enjoyment. Art. 47-3 lets the owner of a program copy adapt it for use on a computer (not confirmed).
• Locks. Two Japanese laws cover locks. The Copyright Act penalises dealing in tools (Art. 120-2, not confirmed). The Unfair Competition Prevention Act was amended in 2018 to cover licence checks and circumvention services (METI). The maximum penalty is five years in prison and a fine of 5 million yen. No interoperability or preservation exception to Japan's lock rules is known. Japan is the strictest country covered for breaking locks.
• Libraries and archives. Libraries may copy under Art. 31. The National Diet Library receives physical games by legal deposit and holds over 9,600 titles. It has said Switch 2 Game-Key Cards do not qualify (Automaton).
• How long copyright lasts. The author's life plus 70 years, and 70 years from publication for company works, from 30 December 2018 (not confirmed).
• Owners who cannot be found. A licensing scheme for "unmanaged" published works came fully into force on 26 May 2026 (Agency for Cultural Affairs).
• Cases. Nintendo and 54 software makers won an injunction against sellers of R4 flash carts on 27 February 2009. In July 2013 the Tokyo District Court awarded 95,625,000 yen in damages, and the judgment became final in January 2016 (Nintendo). Police arrested sellers of edited Pokémon in February 2021 and of modified Breath of the Wild saves in July 2021 (Nintendo Wire). Everyone sued or arrested in these cases sold commercially.
• Games that shut down. No rule is known.

China

• Studying a program. Art. 17 of the Regulations on the Protection of Computer Software lets a person who installs, displays, transmits or stores software study "the design ideas and principles" without permission or fee (State Council). It does not mention decompiling. The Supreme People's Court's 2020 trade-secret rules accept reverse engineering of a product obtained from public channels as a defence (China IP Law Update).
• Locks. The 2020 Copyright Law, in force from 1 June 2021, bans circumvention in Art. 49. Art. 50 allows circumvention for reverse engineering research of software, as long as no tools are given to others (China Justice Observer).
• Libraries and archives. Art. 24(1)(8) lets libraries, archives, memorial halls, museums and galleries copy works in their collections for preservation.
• How long copyright lasts. 50 years from publication for company works (Art. 23).
• Owners who cannot be found. No scheme is known.
• Other rules. Every game sold in China needs a publishing licence from the National Press and Publication Administration, through a local partner. It approved 1,771 games in 2025 (Niko Partners).
• Games that shut down. No rule is known.

South Korea

• Studying a program. Art. 101-4 of the Copyright Act lets a lawful user decompile a program for interoperability, where the information is not easy to get. The information may not be used for other purposes, given to others, or used to build a substantially similar program (KLRI). Art. 101-3(1)(6) lets a lawful user examine, research or test a program to find its ideas.
• Locks. Art. 104-2 bans circumventing access controls. Its exceptions include reverse analysis of program code. The ministry adds further exceptions by notice, which last three years (Korea Copyright Commission).
• Libraries and archives. Art. 31 allows preservation copies.
• How long copyright lasts. The author's life plus 70 years (not confirmed).
• Owners who cannot be found. The ministry may license such works under Art. 50.
• Cases. In 2024 the Supreme Court upheld a 5 million won fine for a man who ran a private server for GTA San Andreas, a single-player game, and took donations (Inven Global). The offence is in the Game Industry Promotion Act.
• Games that shut down. Korea is the only country in the region with consumer rules for closed games. Standard terms in force from 22 March 2024 give refunds and a route to compensation (Korea Times). They cover money that players spent. They do not give a right to keep playing.

Taiwan

• Studying a program. Taiwan has no decompilation article. Art. 59 of the Copyright Act lets the owner of a lawful copy modify it for use on a machine and keep back-ups for personal use. Art. 65 is a fair use clause (Laws & Regulations Database).
• Locks. Art. 80-2 lists "reverse engineering" among its exceptions. Dealing in tools can bring a year in prison under Art. 96-1.
• Libraries and archives. Art. 48 lets libraries and archives copy to avoid loss.
• How long copyright lasts. 50 years from release for company works (Art. 33).

Hong Kong

• Studying a program. The 1997 copyright bill had a decompilation clause. The legislature deleted it and widened fair dealing for research and private study instead (LegCo minutes). Section 60 allows back-up copies.
• Locks. Dealing in tools has been a crime since 2007. Section 273D excuses circumvention to make an independently created program work with another (CEDB).
• How long copyright lasts. The author's life plus 50 years (not confirmed).
• Cases. In 2002 Nintendo, Sony and Microsoft stopped the retailer Lik Sang from selling mod chips (The Register).

What this means for a project

Every country on this page permits study and observation of a program. In Japan, breaking a lock has no known exception. Selling edited save data has led to arrests. In South Korea, running an online service for a game has led to fines.