Z-Library (abbreviated as z-lib, formerly BookFinder) is a

shadow library Shadow libraries (also pirate libraries or black open access) are online repositories of freely available digital media that are normally paywalled, Digital rights management, access-controlled, or otherwise not readily accessible. Shadow librari ...

project for

file-sharing File sharing is the practice of distributing or providing access to digital media, such as computer programs, multimedia (audio, images and video), documents or electronic books. Common methods of storage, transmission and dispersion include re ...

access to

scholarly journal An academic journal (or scholarly journal or scientific journal) is a periodical publication in which scholarship relating to a particular academic discipline is published. They serve as permanent and transparent forums for the dissemination, scr ...

articles, academic texts and general-interest books. It began as a

mirror A mirror, also known as a looking glass, is an object that Reflection (physics), reflects an image. Light that bounces off a mirror forms an image of whatever is in front of it, which is then focused through the lens of the eye or a camera ...

Library Genesis Library Genesis (shortened to LibGen) is a shadow library project for file-sharing access to scholarly journal articles, academic and general-interest books, images, comics, audiobooks, and magazines. The site enables free access to content th ...

but has expanded dramatically. According to the website's own data released in February 2023, its collection comprised over 13.35million books and over 84.8million articles. Z-Library is particularly popular in

emerging economies An emerging market (or an emerging country or an emerging economy) is a market that has some characteristics of a developed market, but does not fully meet its standards. This includes markets that may become developed markets in the future or we ...

and among academics. In June 2020, Z-Library was visited by around 2.84million users, of whom 14.76% were from the

United States of America The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 states and a federal capital district, Washington, D.C. The 48 contiguo ...

. According to the Alexa Traffic Rank service, Z-Library was ranked as the 8,182th most active website in October 2021. The organization describes itself as "the world's largest

e-book An ebook (short for electronic book), also spelled as e-book or eBook, is a book publication made available in electronic form, consisting of text, images, or both, readable on the flat-panel display of computers or other electronic devices. Al ...

library" and "the world's largest scientific articles store." It operates as a non-profit organization sustained by donations. Besides sharing ebooks, Z-Library announced plans to expand their offerings to include physical paperback books at dedicated "Z-Points" around the globe. Z-Library and its activities are illegal in many jurisdictions. While website seizures reduce the accessibility of the content, it remains available on the

dark web The dark web is the World Wide Web content that exists on darknets ( overlay networks) that use the Internet but require specific software, configurations, or authorization to access. Through the dark web, private computer networks can communica ...

. The legal status of the project, as well as its potential impact on the publishing industry and authors' rights, is a matter of ongoing debate.

Website

The site is financed by user donations that are collected twice a year (September and March) through fundraising. Over the years, various

URL A uniform resource locator (URL), colloquially known as an address on the Web, is a reference to a resource that specifies its location on a computer network and a mechanism for retrieving it. A URL is a specific type of Uniform Resource Identi ...

s and

IP address An Internet Protocol address (IP address) is a numerical label such as that is assigned to a device connected to a computer network that uses the Internet Protocol for communication. IP addresses serve two main functions: network interface i ...

es have been used for Z-Library, as domain names have been confiscated by various legal authorities.

Functionality

Little is known about Z-Library in terms of its operation, management, and commercial status. Notably, Z-Library does not open its full database to the public. Despite that, its database, excluding books from Library Genesis, was mirrored by

Anna's Archive Anna's Archive is an open source search engine for shadow library, shadow libraries that was launched by Anna shortly after law enforcement efforts to Z-Library#United States, shut down Z-Library in 2022. The site aggregates records from major ...

in 2022 and continues to be updated. In March 2019, the Z-Library team claimed to have servers in

Finland Finland, officially the Republic of Finland, is a Nordic country in Northern Europe. It borders Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of Bothnia to the west and the Gulf of Finland to the south, ...

, Germany,

Luxembourg Luxembourg, officially the Grand Duchy of Luxembourg, is a landlocked country in Western Europe. It is bordered by Belgium to the west and north, Germany to the east, and France on the south. Its capital and most populous city, Luxembour ...

Malaysia Malaysia is a country in Southeast Asia. Featuring the Tanjung Piai, southernmost point of continental Eurasia, it is a federation, federal constitutional monarchy consisting of States and federal territories of Malaysia, 13 states and thre ...

Panama Panama, officially the Republic of Panama, is a country in Latin America at the southern end of Central America, bordering South America. It is bordered by Costa Rica to the west, Colombia to the southeast, the Caribbean Sea to the north, and ...

, Russia and the United States. The size of their database is over 220 TB. In an effort to prevent blacklisting of domains (oftentimes by internet providers at the

DNS The Domain Name System (DNS) is a hierarchical and distributed name service that provides a naming system for computers, services, and other resources on the Internet or other Internet Protocol (IP) networks. It associates various informatio ...

-level in accordance with legal procedures), Z-Library used a homepage that did not contain any infringing content but instead listed many working mirror domains for different regions. This strategy proved ineffective, as the domain "z-lib.org" was seized in 2022. In August 2023, Z-Library announced the possible use of browser extensions to help mitigate challenges if the domain name has to change.

Fraudulent domains

Some

phishing Phishing is a form of social engineering and a scam where attackers deceive people into revealing sensitive information or installing malware such as viruses, worms, adware, or ransomware. Phishing attacks have become increasingly sophisticate ...

scams have attempted to impersonate Z-Library by using similar domain names and an identical visual design in order to extract login credentials and ask for donations. In June 2024, the news outlet Cybernews reported the discovery of a leaked database containing the personal data of nearly 10 million users, which had been collected by the scam clone site Z-lib s.

Legal status

Z-Library has cycled through domain names, some of which have been blocked by domain registry operators. Z-Library remains accessible via alternative domains and through the .onion-linked

Tor Tor, TOR or ToR may refer to: Places * Toronto, Canada ** Toronto Raptors * Tor, Pallars, a village in Spain * Tor, former name of Sloviansk, Ukraine, a city * Mount Tor, Tasmania, Australia, an extinct volcano * Tor Bay, Devon, England * Tor ...

network.

United Kingdom

In mid-2015, The Publishers Association, a UK organization, attempted to enact

internet service provider An Internet service provider (ISP) is an organization that provides a myriad of services related to accessing, using, managing, or participating in the Internet. ISPs can be organized in various forms, such as commercial, community-owned, no ...

-level blocks on Z-Library. In late 2015, publisher

Elsevier Elsevier ( ) is a Dutch academic publishing company specializing in scientific, technical, and medical content. Its products include journals such as ''The Lancet'', ''Cell (journal), Cell'', the ScienceDirect collection of electronic journals, ...

filed a successful court request that ordered the registrar of bookfi.org to seize the site's

internet domain The Internet (or internet) is the global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a network of networks that consists of private, publ ...

United States

Some of Z-Library's domains (bookfi.org, booksc.org and b-ok.org) were included in the 2017

Office of the United States Trade Representative The Office of the United States Trade Representative (USTR) is an agency of the United States federal government responsible for developing and promoting United States foreign trade policies. Part of the Executive Office of the President, it ...

report on notorious markets. Z-Library's domains were temporarily blocked in 2021 after a

DMCA The Digital Millennium Copyright Act (DMCA) is a 1998 United States copyright law that implements two 1996 treaties of the World Intellectual Property Organization (WIPO). It criminalizes production and dissemination of technology, devices, or ...

notice issued by Harvard Business Publishing. The domain suspensions were lifted. In October 2022,

TikTok TikTok, known in mainland China and Hong Kong as Douyin (), is a social media and Short-form content, short-form online video platform owned by Chinese Internet company ByteDance. It hosts user-submitted videos, which may range in duration f ...

blocked hashtags related to Z-Library after it gained popularity there, and the

Authors Guild The Authors Guild is the United States' oldest and largest professional organization for writers and provides advocacy on issues of free expression and copyright protection. Since its founding in 1912 as the Authors League of America, it has coun ...

submitted a complaint to the

United States Trade Representative The Office of the United States Trade Representative (USTR) is an agency of the Federal government of the United States, United States federal government responsible for developing and promoting Foreign trade of the United States, United States ...

. On November 3, 2022, over 240 domain names of Z-Library's were seized by the

United States Department of Justice The United States Department of Justice (DOJ), also known as the Justice Department, is a United States federal executive departments, federal executive department of the U.S. government that oversees the domestic enforcement of Law of the Unite ...

and

Federal Bureau of Investigation The Federal Bureau of Investigation (FBI) is the domestic Intelligence agency, intelligence and Security agency, security service of the United States and Federal law enforcement in the United States, its principal federal law enforcement ag ...

in response to a

court order A court order is an official proclamation by a judge (or panel of judges) that defines the legal relationships between the parties to a hearing, a trial, an appeal or other court proceedings. Such ruling requires or authorizes the carrying o ...

, and two Russian nationals associated with the project were arrested on charges related to copyright infringement and money laundering in

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

. When the domains z-lib.org, b-ok.org, and 3lib.net were seized, the DNS servers utilized switched to ns1.seizedservers.com and ns2.seizedservers.com, used commonly in US law enforcement seizures. These servers have switched to Njalla, an anonymous hosting provider. The website continues to be active and accessible through the Tor network and the I2P network, before returning to the regular Internet through private personal domains issued to each user on February 11, 2023. Z-Library seizure

On November 16, 2022, U.S. Attorneys for the Eastern District of New York of the Department of Justice unsealed the indictment for two Russian nationals, Anton Napolsky and Valeriiia Ermakva, who had been placed under house arrest in

on November 3, 2022, pending an extradition hearing. They were charged with criminal copyright infringement,

wire fraud Mail fraud and wire fraud are terms used in the United States to describe the use of a physical (e.g., the U.S. Postal Service) or electronic (e.g., a phone, a telegram, a fax, or the Internet) mail system to defraud another, and are U.S. fede ...

and

money laundering Money laundering is the process of illegally concealing the origin of money obtained from illicit activities (often known as dirty money) such as drug trafficking, sex work, terrorism, corruption, and embezzlement, and converting the funds i ...

for operating the Z-Library website. The indictment pertains to alleged criminal activity taking place from 2018 to 2022, though the pair are suspected to have operated Z-Library for "over a decade". The arrests were accomplished by the FBI with data from Google and Amazon (among other sites), accessed with

search warrants A search warrant is a court order that a magistrate or judge issues to authorize law enforcement officers to conduct a search of a person, location, or vehicle for evidence of a crime and to confiscate any evidence they find. In most countries, ...

, that helped identify the founders of the website. The U.S. lawyers retained as official representatives requested a dismissal of the criminal indictment in June 2023. The two escaped their house arrest in Argentina in July 2024. The presiding judge issued an

Interpol The International Criminal Police Organization – INTERPOL (abbreviated as ICPO–INTERPOL), commonly known as Interpol ( , ; stylized in allcaps), is an international organization that facilitates worldwide police cooperation and crime cont ...

warrant for their arrest, and their whereabouts are unknown. The law enforcement efforts were formally assisted by The Publishers Association along with the

, and reportedly, indirectly by BREIN, a Dutch anti-piracy group. The Authors Guild issued a statement supporting the arrests and commented that it was "one of the biggest breakthroughs in the fight against online criminal e-book piracy to date". The executive director for the Authors Alliance, a group dedicated to increasing access for literature, said, "I certainly don't condone illegal behavior, but I think this seizure and press release highlight how broken our copyright system is". Some authors like Alison Rumfitt have also defended the project, arguing that it provides a valuable service by increasing access to knowledge and promoting education in underprivileged communities. Decreased accessibility to Z-Library and its services has substantially impacted students and researchers in underfunded institutions who rely on its resources for their studies and work. Days after the law enforcement action, a group of anonymous archivists launched

, a search engine that provides access to the contents of Z-Library and other shadow libraries. Many other workarounds to the recent attempts to take down Z-Library have been reported. Some of these purported alternative sites have taken up the top search results and submitted bogus

takedown requests of their own, according to news reports. In May 2023, a new round of domain name seizures was carried out by U.S. authorities. In November 2023, dozens of domains were seized by authorities from the United States and Austria. In January 2024, additional Z-Library domains were reported to have been targeted by publishers. In May 2024, several domain name seizures were carried out by U.S. authorities, including the site's email domain z-lib.se.

Meta lawsuit

In July 2023, authors Richard Kadrey,

Sarah Silverman Sarah Kate Silverman (born December 1, 1970) is an American stand-up comedian, actress, and writer. She first rose to prominence for her brief stint as a writer and cast member on the NBC sketch comedy series ''Saturday Night Live'' during its ...

, and

Christopher Golden Christopher Golden (born July 15, 1967) is an American writer. Early life Golden was born and raised in Massachusetts, where he still lives with his family. He graduated from Tufts University. Career As well as novels, Golden has written com ...

filed a class action lawsuit in the Northern District of California Court accusing Meta of

copyright infringement Copyright infringement (at times referred to as piracy) is the use of Copyright#Scope, works protected by copyright without permission for a usage where such permission is required, thereby infringing certain exclusive rights granted to the c ...

and violation of the

Digital Millennium Copyright Act The Digital Millennium Copyright Act (DMCA) is a 1998 United States copyright law that implements two 1996 treaties of the World Intellectual Property Organization (WIPO). It criminalizes production and dissemination of technology, devices, or ...

by using copyrighted works to train its

Llama The llama (; or ) (''Lama glama'') is a domesticated South American camelid, widely used as a List of meat animals, meat and pack animal by Inca empire, Andean cultures since the pre-Columbian era. Llamas are social animals and live with ...

AI model. The District Court dismissed the authors' claims, but in February 2025 the plaintiffs filed an amended complaint citing internal emails from Meta employees which revealed that the company had torrented 81.7 terabytes of data from shadow libraries, contradicting testimony given in the previous hearing. The dataset included 35.7 terabytes of data from Z-Library and

India

Z-Library's website was banned in India in August 2022 following a court order from the Tis Hazari

district court District courts are a category of courts which exists in several nations, some call them "small case court" usually as the lowest level of the hierarchy. These courts generally work under a higher court which exercises control over the lower co ...

after a complaint stated that the copyrights of ten books (pertaining to the topics of tax and corporate law) were being violated by Z-Library. Internet service providers in India were directed to block the site. The decision to block Z-Library and other shadow libraries has been criticized by some Indian authors, students, academics, and freedom of information activists. On November 5, 2022, the Hindu right wing group Swadeshi Jagran Manch formally objected that the FBI's seizure of the Indian domain name 1lib.in (used by Z-lib) by the District Judge of New York's order without jurisdiction had violated India's sovereignty.

France

In September 2022, it was announced that the (National Publishing Union) in France succeeded in a legal challenge to Z-Library, having filed a complaint against 209 domains and mirror site domains associated with it. They were joined in the challenge by twelve major publishing houses:

Actes Sud Actes Sud is a French publishing house based in Arles. It was founded in 1978 by author Hubert Nyssen. By 2013, the company, then headed by Nyssen's daughter, Françoise Nyssen, had an annual turnover of 60 million euros and 60 staff members. ...

Albin Michel Albin may refer to: Places * Albin, Wyoming, US * Albin Township, Brown County, Minnesota, US * Albin, Virginia, US People * Albin (given name), origin of the name and people with the first name "Albin" * Albin (surname) ;Mononyms * Albin of ...

Cairn A cairn is a human-made pile (or stack) of stones raised for a purpose, usually as a marker or as a burial mound. The word ''cairn'' comes from the (plural ). Cairns have been and are used for a broad variety of purposes. In prehistory, t ...

, Editis,

Hachette Livre Hachette Livre S.A. (; simply known as Hachette) is a French publishing, publishing group that was based in Paris. It was founded in 1826 by Louis Hachette as Brédif which later became successively L. Hachette et Compagnie, Librairie Hachette, ...

, Humensis, Lefebvre-Sarrut,

LexisNexis LexisNexis is an American data analytics company headquartered in New York, New York. Its products are various databases that are accessed through online portals, including portals for computer-assisted legal research (CALR), newspaper searc ...

, Madrigall, Maison des Langues, Odile Jacob, and Presses de Science Po. The decision was made by the Tribunal Judiciaire de Paris, which is Paris's civil court; internet service providers in France were directed to block the domains. Z-library sites and content began to reappear online after the 2022 court decision. In September 2024, the Tribunal Judiciaire de Paris issued another court order requiring internet service providers to block an additional 98 domains.

China

The site is targeted and blocked by the Great Firewall. In April 2024, Z-Library announced that their Chinese social media accounts, including those on

WeChat WeChat or Weixin in Chinese ( zh, c=微信, p=Wēixìn , l=micro-message) is an instant messaging, social media, and mobile payment mobile app, app developed by Tencent. First released in 2011, it became the world's largest standalone mobile a ...

and

Bilibili Bilibili (stylized in all lowercase), nicknamed B Site, is a Chinese online video sharing website based in Shanghai where users can submit, view, and add overlaid commentary on videos. Bilibili hosts videos on various themes, including ...

, would be shut down in response to alleged "attacks" against volunteers by the Chinese judicial system.

References

{{Portal bar, Books, Education Book websites File sharing communities Intellectual property activism Internet censorship in India Internet censorship in the United States Internet properties established in 2009 Russian digital libraries Search engine software Shadow libraries Domain name seizures by United States Internet-related controversies