Wikipedia Describes CERN: Disagreements | Network, Not Protocol

On November 12, 2026, Mark Nichols set the Wikipedia article CERN, as revised on November 8, 2026, against dated documents and found that the article itself calls CERN's TCP/IP network of 1984 "its intranet," that CERN's own record says that CERN restricted TCP/IP "for use within the CERN site" until January 1989, and that the article's account of the World Wide Web at CERN dates its invention to 1989, its first website to 1991 and its release to the public domain to "the World Wide Web" as a whole, where the documents record a proposal in March 1989, an origin of the Web in 1990 in Berners-Lee's own words and a release of three components of Web software on 30 April 1993.

Preamble: I created this page to examine how the Wikipedia article CERN, in its revision of November 8, 2026, describes the network of CERN and the work at CERN that produced the World Wide Web. The page records that the article calls CERN's TCP/IP network of 1984 "its intranet" and calls the laboratory "a major wide area network hub," and it tests the article's statements that "In 1989, the World Wide Web was invented at CERN by Tim Berners-Lee," that the Web was "Based on the concept of hypertext," that ENQUIRE was "a database," that "The first website was activated in 1991," that "On 30 April 1993, CERN announced that the World Wide Web would be free to anyone," and that CERN hosts one of the main "internet exchange points" in Switzerland. The page sets the article against Ben Segal's history of the Internet protocols at CERN as CERN published it in 2014, against Tim Berners-Lee's proposal of March 1989, against the papers that Berners-Lee wrote with his colleagues in 1992 and 1994, against the finding aid of the CERN Archives for the archives of the World Wide Web and against CERN's own account of the statement of 30 April 1993. Each disagreement on this page cites the article's line by its number in Exhibit A in section 9.0 and names the dated document that decides it. Wikipedia, CERN, revision 1384478899 · Wikipedia Describes Tim Berners-Lee: Disagreements | Network, Not Protocol · The Governing Definitions and Controlling Facts of Telecommunications Internetworking. This page is Disagreement 68 in the standing index of the series, Disagreements of Published Claims | Network, Not Protocol, and a finding on this page is cited by that number followed by the finding's locus, as Disagreement 68, 1.1.

Opinion Rules: You are visiting my record, and I am the subject matter expert on it. If you are a subject matter expert too, I want to hear from you: bring your document and I will answer it on the record. If you are not, you are welcome here to read and to learn. The documented-challenge terms of marknichols.com and the condition on opinion are stated at F40 of The Governing Definitions and Controlling Facts of Telecommunications Internetworking, and they govern this page.

0.0 This section records the revision of the Wikipedia article this page examines, the documents this page read, the way the line numbers on this page are read, the definitions and rules the findings apply, the audit of the article as an authority, and the order of the sections that follow.

0.1 This page examines the Wikipedia article CERN on en.wikipedia.org in revision 1384478899. Wikipedia's revision history records that revision 1384478899 was saved on November 8, 2026 at 12:16 (UTC), which is November 8, 2026 in Pacific time, by the account "Spartaz," with the edit summary "Removing link(s) because [[Wikipedia:Articles for deletion/List of streets at CERN]] closed as delete ([[WP:XFDC#4.0.16|XFDcloser]])." Wikipedia's page information for the article, read on November 12, 2026, recorded revision 1384478899 as the latest revision of the article and recorded that editing is restricted to autoconfirmed accounts and moving to administrators. The revision of November 8, 2026 removed links, and the accounts that wrote the sentences this page answers are not recorded in the revision this page reproduces, so the accounts that wrote those sentences are stated on this page as unknown. The text of the article is attributed to Wikipedia contributors under CC BY-SA 4.0.

0.2 This page read the following documents in full on November 12, 2026, and it states for each document that it did not read that the document was not read.

  1. Ben Segal, "Internet prehistory at CERN," published by CERN on home.cern on 9 April 2014 as "an edited and abridged version of Ben Segal’s “Short History of Internet Protocols at CERN“," was read in full. Segal's unabridged history of 1995, which the article cites at lines 53 and 54, was not read, because the copy on Segal's CERN web page did not load.
  2. Tim Berners-Lee's proposal "Information Management: A Proposal," dated March 1989, was read in full in the annotated scan held in the CERN Archives as CERN-ARCH-WWW-04-010.
  3. Tim Berners-Lee, Robert Cailliau, Jean-François Groff and Bernd Pollermann, "World-Wide Web: The Information Universe," of 1992, was read in full in the authors' text.
  4. Tim Berners-Lee, Robert Cailliau, Ari Luotonen, Henrik Frystyk Nielsen and Arthur Secret, "The World-Wide Web," in Communications of the ACM, Volume 37, Number 8, August 1994, pages 76 to 82, was read in full in its reprint in the ACM book of 2023 Linking the World’s Information: Essays on Tim Berners-Lee’s Invention of the World Wide Web.
  5. The finding aid of the CERN Archives for the archives of the World Wide Web, CERN-ARCH-WWW, updated in February 2022, was read in full.
  6. Tim Smith and François Flückiger, "Licensing the Web," on home.cern, was read in full. The statement of 30 April 1993 itself was not read, because the CERN Document Server that holds it placed an automated bot check in front of the record, and this page quotes the statement only in the words that CERN's page quotes.
  7. The other sources that the article cites, including James Gillies and Robert Cailliau's book How the Web was Born of 2000 and Stephanie Sammartino McPherson's book Tim Berners-Lee: Inventor of the World Wide Web of 2009, were not read, and this page makes no finding on them.

0.3 Each line number on this page refers to Exhibit A in section 9.0. Exhibit A lists the text of revision 1384478899 line by line, in the order the article prints it, under the names of the article's own sections. Each disagreement also quotes the line it answers.

0.4 The capital-I Internet (D1) is the publicly joinable network of networks of the registry lineage, whose addresses and autonomous system numbers were issued by the InterNIC and are maintained today by ARIN. On that network, a person can buy access from competing providers for lawful purposes, and an independent network can obtain addresses and an autonomous system number and interconnect by agreement with a willing network, without the permission of a central owner or the sponsorship of a government. An intranet (D2) is a network, at any scale and under any protocol, whose members join by an owner's permission. A lowercase internet (D11) is any interconnection of networks, including gated ones, and the capital I in this site's own prose means the publicly joinable network of the registry lineage born in 1991 and nothing else. The World Wide Web is an application that runs across the Internet platform. Governing Definitions, D1, D2, and D11.

0.5 This page answers three kinds of disagreement, and each disagreement on this page names the kind that applies.

  1. A documentary contradiction occurs when a dated record conflicts with a line as written. This page answers it with the dated record and a dated correction.
  2. A scope overstatement occurs when the evidence establishes a narrower event, network, date or function than the line claims. This page answers it with the scope the evidence establishes.
  3. A definitional disagreement occurs when the article and this site apply different criteria to the same term. This page answers it by attributing each usage to its source.

0.6 The article has no author of record. This page applies to it the five checks that Mark Nichols ruled on October 2, 2026, and extended on October 23, 2026, for every authority a page cites or disputes, and the five checks return the following results.

  1. The issuing body's membership rule is Wikipedia's editing rule, and Wikipedia's page information of November 12, 2026 recorded that editing of the article is restricted to autoconfirmed accounts.
  2. The roster on the date of the act is the account that saved revision 1384478899, the account "Spartaz," whose edit removed links, and the accounts that wrote the sentences this page answers are not recorded in that revision, so this record states them as unknown.
  3. The instrument carries no named author and no vote, because a Wikipedia revision is saved by one account and adopted by no body.
  4. The custodian is the Wikimedia Foundation, which serves the article at en.wikipedia.org as a text that changes with every saved revision, so the article is a living text and not a dated instrument, which is why 0.1 fixes the revision by its number and its date.
  5. The overlap between the article's authors and the author of this page cannot be computed, because this page names its author, Mark Nichols, and the article names no author. The overlap between the subject and the sources is recorded here as a finding: the paragraph of the article that ends with line 24, "CERN is also the birthplace of the World Wide Web," cites James Gillies and Robert Cailliau's book How the Web was Born, and Robert Cailliau is the colleague of Tim Berners-Lee whom the article's line 58 names as "involved in 1990." This page makes no finding on why the overlap exists.

Under D12, contemporaneous primary documents control over retrospective accounts. The article is a retrospective account with no author of record, so no line of the article is carried on this page as controlling. Every disagreement below is decided by the dated document that the disagreement names, and not by the standing of the article. Governing Definitions, D12.

0.7 Under F56, Mark Nichols ruled on October 23, 2026 that a sentence of history or of definition is true or false as written. This page reads every line of the article as written, and it reads every document that it quotes as written by the person who wrote it. A line whose predicate is false as written is false, whether the falsity arose from compression, from shorthand or from intent. Each corrected statement on this page supplies the network, the document, the date or the event that the line left out. Governing Definitions, F56.

0.8 Sections 1.0 through 6.0 each record one finding, in the order of the article's own lines.

  1. Section 1.0 records the network of CERN as the article describes it at lines 23, 53 and 54 and as CERN's own record describes it.
  2. Section 2.0 answers line 55, "In 1989, the World Wide Web was invented at CERN by Tim Berners-Lee."
  3. Section 3.0 answers lines 56 and 57, the Web "Based on the concept of hypertext" and ENQUIRE described as "a database."
  4. Section 4.0 answers line 61, "The first website was activated in 1991."
  5. Section 5.0 answers line 62, "On 30 April 1993, CERN announced that the World Wide Web would be free to anyone."
  6. Section 6.0 answers line 65, which calls the CERN Internet Exchange Point one of "the two main internet exchange points in Switzerland."

Section 7.0 records the statements of the article that the documents support. Section 8.0 states the findings of this page and their consequences for the article as an authority. Section 9.0 holds Exhibit A, the numbered text of revision 1384478899.

1.0 The article calls CERN's TCP/IP network of 1984 "its intranet" at line 53 and calls the laboratory "a major wide area network hub" at line 23, which agrees with D2 and with CERN's own record, because Ben Segal wrote for CERN that CERN restricted TCP/IP "for use within the CERN site" until it "opened its first external connections to the internet" in January 1989.

1.1 Line 23 of the article says: "As researchers require remote access to these facilities, the lab has historically been a major wide area network hub." Line 53 says: "CERN pioneered the introduction of TCP/IP for its intranet, beginning in 1984." Line 54 says: "This played an influential role in the adoption of the TCP/IP in Europe (see History of the Internet and Protocol Wars)."

1.2 Mark Nichols records lines 23 and 53 as agreeing with D2 and with CERN's own record. The article names the network of CERN as a wide area network hub and names CERN's TCP/IP network of 1984 as an intranet, and CERN's own history says that the TCP/IP network stayed inside the CERN site until January 1989. This is a documentary finding that supports the article.

1.3 Ben Segal, a CERN computer scientist, wrote "Internet prehistory at CERN," which CERN published on home.cern on 9 April 2014. Segal's article records the following events in his own words.

  1. Segal wrote: "In August 1984 I wrote a proposal to SW group leader, Les Robertson, for the establishment of a pilot project to install and evaluate TCP/IP protocols on some key non-Unix machines at CERN including the central IBM-VM mainframe and a VAX VMS system."
  2. Segal wrote: "In early 1985 I was appointed the “TCP/IP Coordinator” for CERN, as part of a formal agreement between SW group and DC group."
  3. Segal wrote: "DC’s policy specifically restricted the internet protocols for use within the CERN site. No external connections were to be made using TCP/IP: here the ISO/IBM/DECnet monopoly still ruled supreme, and would do so until early 1989."
  4. Segal wrote: "November 1985 brought a major step forward when LEP’s management decided to use TCP/IP for the control system on the 27-kilometre Large Electron-Positron Collider (LEP)."
  5. Segal wrote: "CERN opened its first external connections to the internet after a “big bang” in January 1989 to change all IP addresses to official ones."

Ben Segal, "Internet prehistory at CERN," home.cern, 9 April 2014.

1.4 Under D2, a network whose members join by an owner's permission is an intranet at any scale and under any protocol, so the TCP/IP network inside the CERN site from 1985 to January 1989 was an intranet, as line 53 says. Segal's article does not name the external network or networks that CERN joined in January 1989, so the name of that network is unknown on this record. The network outside CERN in 1989 and 1990 was a research internetwork, an internet in lowercase under D11, and the Internet, with a capital I, was born in 1991 under D1. Line 54 credits CERN with a role in the adoption of a protocol in Europe and does not credit the protocol with a network, and Segal's abridged article does not address the adoption of TCP/IP in Europe, so this page makes no finding on line 54. Governing Definitions, D1, D2, and D11.

1.5 This section records lines 23 and 53 as supported at the scope stated in 1.4 and counts no line of the article as false.

1.6 Corrected statement: From 1985 to January 1989, CERN ran TCP/IP only within its own site, as an intranet under D2, and in January 1989 CERN opened its first external TCP/IP connections to the research internetwork, an internet in lowercase under D11, through a network whose name is unknown on this record.

2.0 Line 55 says that "In 1989, the World Wide Web was invented at CERN by Tim Berners-Lee," which is false as written in its verb and a documentary finding in its date, because the World Wide Web application design is a label for a large body of technology made by many persons and bodies inside and outside CERN, as F32.4 of The Governing Definitions states, because the document of 1989 is a proposal, the finding aid of the CERN Archives says that prototype software was ready by the end of 1989 and refined in 1990, and Berners-Lee's own paper of 1994 says that he "originated the World-Wide Web in 1990."

2.1 Line 55 of the article says: "In 1989, the World Wide Web was invented at CERN by Tim Berners-Lee."

2.2 Mark Nichols records the date and the verb as findings. Under the ruling of Mark Nichols of November 13, 2026, a sentence saying that Tim Berners-Lee invented the World Wide Web is false as written, as F32.4 of The Governing Definitions states, so the verb of line 55 is false as written. The dated documents disagree on whether the World Wide Web existed in 1989 or in 1990, and the document that Berners-Lee wrote in 1989 is a proposal for a system, which is a documentary finding on the date.

2.3 The documents record the following.

  1. Tim Berners-Lee's "Information Management: A Proposal" is dated "March 1989" in its heading, and its abstract says: "It discusses the problems of loss of information about complex evolving systems and derives a solution based on a distributed hypertext sytstem." The word "sytstem" is printed so in the proposal.
  2. The finding aid of the CERN Archives says: "The first proposal for the World Wide Web (WWW) was made at CERN by Tim Berners-Lee in 1989. With the support of his boss Mike Sendall (leader of the Online Computing group in CERN’s Data Handling division from 1985) prototype software for a basic system was ready by the end of the year; it was further refined by Tim Berners-Lee and Robert Cailliau in 1990."
  3. The paper of August 1994 by Berners-Lee and his colleagues prints in its section "About the Authors": "TIM BERNERS-LEE originated the World-Wide Web in 1990 to enable the sharing of knowledge by complex distributed teams."
  4. Berners-Lee's paper of 1992 with Cailliau, Groff and Pollermann says: "Merging the techniques of hypertext, information retrieval, and wide-area networking produces the W3 model."

2.4 This section counts line 55 among the false-as-written verdicts on its verb, and it records a documentary finding on its date. The records place the proposal in March 1989, the prototype software at the end of 1989 and the origin of the World Wide Web, in Berners-Lee's own paper of 1994, in 1990, and Berners-Lee's paper of 1992 describes the Web as a merging of existing techniques. The same record is answered on Wikipedia Describes Tim Berners-Lee: Disagreements | Network, Not Protocol in its sections 1.0 and 2.0.

2.5 Corrected statement: Tim Berners-Lee proposed a distributed hypertext system at CERN in March 1989, prototype software was ready by the end of 1989 according to the finding aid of the CERN Archives, Berners-Lee and Robert Cailliau refined the software in 1990, and Berners-Lee's paper of August 1994 says that he originated the World-Wide Web in 1990, and the World Wide Web application design is a label for a large body of technology made by many persons and bodies inside and outside CERN, as F32.4 of The Governing Definitions states.

3.0 Lines 56 and 57 say that the Web was "Based on the concept of hypertext" and stemmed from "a database named ENQUIRE," which is a documentary finding, because the article names no source for the concept while CERN's own published history says that Berners-Lee was "influenced by Ted Nelson’s work on Xanadu among other things," and because the only description of ENQUIRE that this page read is Berners-Lee's own, which calls it "a small linked information system."

3.1 Line 56 of the article says: "Based on the concept of hypertext, the idea was designed to facilitate information sharing between researchers." Line 57 says: "This stemmed from Berners-Lee's earlier work at CERN on a database named ENQUIRE." The article names no person or system as the source of the concept of hypertext.

3.2 Mark Nichols records the omission and the description as a finding. The concept of hypertext has dated authors, CERN's own published history names Ted Nelson's Xanadu, and ENQUIRE is known on this record only from Berners-Lee's own description. This is a documentary finding on the article and on the record of credit.

3.3 Ben Segal's article, published by CERN on home.cern on 9 April 2014, says: "Tim’s first web proposal was written immediately after the opening of CERN’s first external connection and Tim had been working with hypertext ideas since 1980, influenced by Ted Nelson’s work on Xanadu among other things." The full record of the hypertext systems that came before the World Wide Web, from Vannevar Bush in July 1945, Theodor H. Nelson in 1965 and Douglas C. Engelbart and William K. English in 1968 to Andries van Dam's keynote in Communications of the ACM of July 1988, which Berners-Lee's proposal of March 1989 cites, is set out in section 3.0 of Wikipedia Describes Tim Berners-Lee: Disagreements | Network, Not Protocol.

3.4 Berners-Lee's proposal of March 1989 describes ENQUIRE on its page 5 in three sentences.

  1. The proposal says: "It was for these reasons that I first made a small linked information system, not realising that a term had already been coined for the technique: "Hypertext"."
  2. The proposal says: "In 1980, I wrote a program for keeping track of software with which I was involved in the PS control system."
  3. The proposal says: "Called Enquire, it allowed one to store snippets of information, and to link related pieces together in any way."

This page read no copy of the ENQUIRE software and no document other than Berners-Lee's own proposal that describes ENQUIRE, so the existence and the function of ENQUIRE rest on this record on Berners-Lee's own account.

3.5 This section records a documentary finding and does not count lines 56 and 57 among the false-as-written verdicts.

3.6 Corrected statement: The World Wide Web was based on the concept of hypertext, which Theodor H. Nelson named in 1965 and which, by CERN's own published history, influenced Berners-Lee through "Ted Nelson’s work on Xanadu among other things," and Berners-Lee's proposal of March 1989 describes his earlier program ENQUIRE, written at CERN in 1980, as "a small linked information system," of which this record holds no surviving copy.

4.0 Line 61 says that "The first website was activated in 1991," which is a documentary finding, because the Wikipedia article Tim Berners-Lee dates the first website to 20 December 1990, the finding aid of the CERN Archives dates to 1991 the release of an early WWW system to the high energy physics community, and no document this page read dates the first website.

4.1 Line 61 of the article says: "The first website was activated in 1991." Line 62 of the Wikipedia article Tim Berners-Lee, in revision 1384351970 of November 7, 2026, says: "Berners-Lee published the first website, which described the project itself, on 20 December 1990; it was available to the Internet from the CERN network."

4.2 Mark Nichols records the date as a finding. Two articles of Wikipedia give two different years for the same website, and the documents that this page read do not date the first website. This is a documentary finding on the date.

4.3 The finding aid of the CERN Archives says: "In 1991, an early WWW system was released to the high energy physics community via the CERN program library." The finding aid continues: "It included the simple browser, web server software and a library, allowing developers to build their own software." The finding aid says of the first servers: "The first web servers were all located in European physics laboratories and only a few users had access to the NeXT platform on which the first browser ran." The sources that line 61 and the article Tim Berners-Lee cite were not read, as 0.2 records.

4.4 This section records a documentary finding and does not count line 61 among the false-as-written verdicts, because the two articles of Wikipedia disagree and this page has not read the document that would decide between them.

4.5 Corrected statement: Wikipedia dates the first website to 20 December 1990 in its article Tim Berners-Lee and to 1991 in its article CERN, and the finding aid of the CERN Archives dates to 1991 the release of an early WWW system, with a browser, web server software and a library, to the high energy physics community through the CERN program library.

5.0 Line 62 says that "On 30 April 1993, CERN announced that the World Wide Web would be free to anyone," which is a scope overstatement, because CERN's own account says that the statement of 30 April 1993 put "the three components of Web software (the basic line-mode client, the basic server and the library of common code)" in the public domain.

5.1 Line 62 of the article says: "On 30 April 1993, CERN announced that the World Wide Web would be free to anyone."

5.2 Mark Nichols disputes the scope of "the World Wide Web." The statement of 30 April 1993 released three pieces of CERN software, and the World Wide Web as a system, with its servers, its documents and the networks that carry it, was not CERN's to announce as free. This is a scope overstatement.

5.3 Tim Smith and François Flückiger, in "Licensing the Web" on home.cern, say: "On 30 April 1993 CERN issued a public statement stating that the three components of Web software (the basic line-mode client, the basic server and the library of common code) were put in the Public Domain with the statement:" The statement that the page quotes reads: "CERN relinquishes all intellectual property rights to this code, both source and binary and permission is given to anyone to use, duplicate, modify and distribute it." The finding aid of the CERN Archives says: "In April 1993 CERN issued a statement putting the Web software in the public domain." CERN's page also records that on 15 November 1994 François Flückiger announced that later versions of the software "will remain copyrighted by CERN."

5.4 This section records a scope overstatement and does not count line 62 among the false-as-written verdicts.

5.5 Corrected statement: On 30 April 1993, CERN put three components of its Web software, the basic line-mode client, the basic server and the library of common code, into the public domain, relinquishing "all intellectual property rights to this code," and on 15 November 1994 CERN announced that later versions of its Web software would remain copyrighted by CERN while staying freely available.

6.0 Line 65 calls the CERN Internet Exchange Point "one of the two main internet exchange points in Switzerland," which is a definitional disagreement under D1 and D11, because an exchange point of the Internet is an exchange point of the capital-I Internet and not of an internet in lowercase.

6.1 Line 65 of the article says: "It also hosts the CERN Internet Exchange Point (CIXP), one of the two main internet exchange points in Switzerland."

6.2 Mark Nichols disputes the lowercase "internet" in "internet exchange points." The line names the exchange point with a capital I, as "the CERN Internet Exchange Point," and describes the same class of exchange in lowercase. This is a definitional disagreement under D1 and D11.

6.3 Under D11, a lowercase internet is any interconnection of networks, including gated ones, and under D1 the capital-I Internet is the publicly joinable network of networks of the registry lineage born in 1991. An exchange point at which independent networks of the registry lineage interconnect by agreement is an exchange point of the Internet, and the line itself writes the proper name of CERN's exchange point with a capital I. The source that line 65 cites was not read, and the date on which the CERN Internet Exchange Point was established is not stated in any document this page read. Governing Definitions, D1 and D11.

6.4 This section records a definitional disagreement under D1 and D11 and does not count line 65 among the false-as-written verdicts.

6.5 Corrected statement: CERN hosts the CERN Internet Exchange Point (CIXP), one of the two main Internet exchange points in Switzerland.

7.0 The article states several things correctly that this page checked, and the documents that support each one are named here.

7.1 Line 24 says: "CERN is also the birthplace of the World Wide Web." The line is supported. The finding aid of the CERN Archives says: "The first proposal for the World Wide Web (WWW) was made at CERN by Tim Berners-Lee in 1989." The paper of August 1994 describes the Web as expanding "from its origins at CERN across the Internet."

7.2 Line 58 says: "A colleague, Robert Cailliau, became involved in 1990." The line is supported. The finding aid of the CERN Archives says that the prototype software "was further refined by Tim Berners-Lee and Robert Cailliau in 1990."

7.3 Lines 23 and 53 are supported at the scope stated in section 1.0. Line 52, line 59 on the honour of 1995 from the Association for Computing Machinery and line 63 on the Web as "the dominant way through which most users interact with the Internet" were not checked against a document, and this page makes no finding on them.

8.0 One statement of the Wikipedia article CERN is false as written, line 55 in its verb, six findings record one documentary finding in support of the article, three further documentary findings, one of them on the date of line 55, one scope overstatement and one definitional disagreement, and the article is not carried on marknichols.com as an authority on the history of the World Wide Web or of the Internet.

8.1 The following statement of revision 1384478899 is false as written under F56. It is decided by the ruling and the documents named in the section cited.

  1. Line 55 says that "the World Wide Web was invented at CERN by Tim Berners-Lee," while the World Wide Web application design is a label for a large body of technology made by many persons and bodies inside and outside CERN, as F32.4 of The Governing Definitions states and as section 2.0 records.

8.2 Six findings record the following.

  1. Lines 23 and 53 call CERN "a major wide area network hub" and its TCP/IP network of 1984 "its intranet," which agrees with D2 and with Ben Segal's history as CERN published it, as section 1.0 records.
  2. Line 55 dates the work it describes to 1989, while the record holds a proposal of March 1989 and Berners-Lee's own statement that he "originated the World-Wide Web in 1990," which is a documentary finding, as section 2.0 records.
  3. Lines 56 and 57 name no source for the concept of hypertext and call ENQUIRE "a database," while CERN's own published history names "Ted Nelson’s work on Xanadu" and ENQUIRE is known on this record only from Berners-Lee's own account, which is a documentary finding, as section 3.0 records.
  4. Line 61 dates the first website to 1991, while the Wikipedia article Tim Berners-Lee dates the first website to 20 December 1990, which is a documentary finding, as section 4.0 records.
  5. Line 62 says that CERN announced "that the World Wide Web would be free to anyone," while CERN's own account says that the statement of 30 April 1993 released three components of Web software, which is a scope overstatement, as section 5.0 records.
  6. Line 65 writes "internet exchange points" in lowercase for the exchange points of the Internet, which is a definitional disagreement under D1 and D11, as section 6.0 records.

8.3 Under D12, contemporaneous primary documents control over retrospective accounts, and this page has decided each finding by the following documents.

  1. Tim Berners-Lee's "Information Management: A Proposal," dated March 1989 and held in the CERN Archives as CERN-ARCH-WWW-04-010, proposes "a distributed hypertext sytstem" and describes ENQUIRE as "a small linked information system."
  2. "World-Wide Web: The Information Universe," by Berners-Lee, Cailliau, Groff and Pollermann, of 1992, describes the Web as the merging of hypertext, information retrieval and wide-area networking.
  3. "The World-Wide Web," by Berners-Lee, Cailliau, Luotonen, Nielsen and Secret, in Communications of the ACM of August 1994, dates the origin of the Web to 1990.
  4. The finding aid of the CERN Archives for CERN-ARCH-WWW, updated in February 2022, dates the prototype software to the end of 1989, its refinement to 1990, the release of an early WWW system to the high energy physics community to 1991 and CERN's statement putting the Web software in the public domain to April 1993.
  5. Ben Segal's "Internet prehistory at CERN," published by CERN on 9 April 2014, records that CERN restricted TCP/IP to the CERN site until January 1989.
  6. Tim Smith and François Flückiger's "Licensing the Web," on home.cern, records the three components of Web software released on 30 April 1993.

The Wikipedia article CERN is a retrospective account with no author of record, the article names no source for the concept of hypertext on which the article says the Web was based, and the article's statement that CERN is the birthplace of the World Wide Web cites a book co-written by Robert Cailliau, whom the article names as a participant. No line of the article is carried on marknichols.com as controlling. Governing Definitions, D12.

8.4 The findings on this page are open to challenge on the terms stated at F40 of The Governing Definitions and Controlling Facts of Telecommunications Internetworking. A challenger who holds that a finding on this page is wrong states the competing claim in one sentence, names the document that carries it and the document's date, and submits both as F40 directs. A challenge submitted with its document is answered on this page, and a challenge submitted without a document is an opinion and is heard as one.

9.0 This section holds Exhibit A, the numbered text of the Wikipedia article CERN in revision 1384478899 of November 8, 2026.

9.1 Exhibit A reproduces the text of revision 1384478899 line by line, under the names of the article's own sections, so that every line number cited on this page can be read in place.

  1. The exhibit includes the article's short description, the rows of its infobox, with each label separated from its value by a vertical bar, the captions of its images, its body sentences, its list items, the rows of its tables, with the cells of each row separated by vertical bars, and its maintenance notice, and it heads the article's opening section, which the article prints without a heading, with the word "Lead."
  2. The exhibit omits the article's hatnotes, its footnote markers, its explanatory notes, the navigation of Wikipedia, the sections "See also," "References," "Further reading" and "External links," and the footer.
  3. The exhibit prints every line as the article prints it, including the tag "[update]" that the article prints in line 66.

The text is quoted from Wikipedia under CC BY-SA 4.0. Wikipedia, CERN, revision 1384478899.

Exhibit A: Wikipedia, CERN, revision 1384478899 of November 8, 2026

Short description

1. European particle physics research centre

Infobox

2. Organisation européenne pour la recherche nucléaire

3. CERN's main site in Meyrin, Switzerland, looking towards the French border

4. States with full CERN membership

5. Formation | 29 September 1954; 72 years ago (1954-09-29)

6. Headquarters | Meyrin, Geneva, Switzerland46°13′59″N 6°03′20″E / 46.2330°N 6.0556°E / 46.2330; 6.0556

7. Members | Full members (25): Austria Belgium Bulgaria Czech Republic Denmark Estonia Finland France Germany Greece Hungary Israel Italy Netherlands Norway Poland Portugal Romania Serbia Slovakia Slovenia Spain Sweden Switzerland United Kingdom Associate members (11): Brazil Chile Croatia Cyprus India Ireland Latvia Lithuania Pakistan Turkey Ukraine

8. Official languages | English and French

9. Council President | Costas Fountas [de]

10. Director-General | Mark Thomson

11. Budget | 1515m CHF (2026)

12. Website | home.cern

Lead

13. The European Organization for Nuclear Research, also called European Laboratory for Particle Physics, known as CERN (/sɜːrn/; French pronunciation: [sɛʁn]; Organisation européenne pour la recherche nucléaire), is an intergovernmental organization that operates the largest particle physics laboratory in the world.

14. Established in 1954, it is based in Meyrin, a western suburb of Geneva, on the France–Switzerland border.

15. It comprises 25 member states.

16. Israel, admitted in 2013, is the only full member geographically out of Europe.

17. CERN is an official United Nations General Assembly observer.

18. The acronym CERN is also used to refer to the laboratory; in 2024, it had 2,704 scientific, technical, and administrative staff members, and hosted about 12,406 users from institutions in more than 80 countries.

19. In 2016, CERN generated 49 petabytes of data.

20. CERN's main function is to provide the particle accelerators and other infrastructure needed for high-energy physics research – consequently, numerous experiments have been constructed at CERN through international collaborations.

21. CERN is the site of the Large Hadron Collider (LHC), the world's largest and highest-energy particle collider.

22. The main site at Meyrin hosts a large computing facility, which is primarily used to store and analyze data from experiments, as well as simulate events.

23. As researchers require remote access to these facilities, the lab has historically been a major wide area network hub.

24. CERN is also the birthplace of the World Wide Web.

History

25. The convention establishing CERN was ratified on 29 September 1954 by 12 countries in Western Europe.

26. The acronym CERN originally represented the French words for Conseil Européen pour la Recherche Nucléaire ('European Council for Nuclear Research'), which was a provisional council for building the laboratory, established by 12 European governments in 1952.

27. During these early years, the council worked at the University of Copenhagen under the direction of Niels Bohr before moving to its present site near Geneva.

28. The acronym was retained for the new laboratory after the provisional council was dissolved, even though the name changed to the current Organisation européenne pour la recherche nucléaire ('European Organization for Nuclear Research') in 1954.

29. According to Lew Kowarski, a former director of CERN, when the name was changed, the abbreviation could have become the awkward OERN, and Werner Heisenberg said that this could "still be CERN even if the name is [not]".

30. CERN's first president was Sir Benjamin Lockspeiser.

31. Edoardo Amaldi was the general secretary of CERN at its early stages when operations were still provisional, and the first Director-General (1954) was Felix Bloch.

Founding members

32. The 12 founding member states of CERN in 1954

33. At the sixth session of the CERN Council in Paris from 29 June to 1 July 1953, the convention establishing the organization was signed, subject to ratification, by 12 states.

34. The convention was gradually ratified by the 12 founding Member States: Belgium, Denmark, France, the Federal Republic of Germany, Greece, Italy, the Netherlands, Norway, Sweden, Switzerland, the United Kingdom, and Yugoslavia.

Scientific achievements

35. Several major achievements in particle physics have occurred in experiments at CERN.

36. They include:

37. 1973: The discovery of neutral currents in the Gargamelle bubble chamber

38. 1983: The discovery of W and Z bosons in the UA1 and UA2 experiments

39. 1989: The determination of the number of light neutrino families at the Large Electron–Positron Collider (LEP) operating on the Z boson peak

40. 1995: The first creation of antihydrogen atoms in the PS210 experiment

41. 1995–2005: Precision measurement of the Z lineshape, based predominantly on LEP data collected on the Z resonance from 1990 to 1995

42. 1999: The discovery of direct CP violation in the NA48 experiment

43. 2000: The Heavy Ion Programme discovered a new state of matter, quark–gluon plasma.

44. 2010: The isolation of 38 atoms of antihydrogen

45. 2011: Maintaining antihydrogen for over 15 minutes

46. 2012: The discovery of a boson with mass around 125 GeV/c2 consistent with the long-sought Higgs boson

47. In September 2011, CERN attracted media attention when the OPERA Collaboration reported the detection of possibly faster-than-light neutrinos.

48. Further tests showed that the results were flawed due to an incorrectly connected GPS synchronization cable.

49. The 1984 Nobel Prize for Physics was awarded to Carlo Rubbia and Simon van der Meer for the developments that resulted in the discoveries of the W and Z bosons.

50. The 1992 Nobel Prize for Physics was awarded to CERN staff researcher Georges Charpak "for his invention and development of particle detectors, in particular the multiwire proportional chamber".

51. The 2013 Nobel Prize for Physics was awarded to François Englert and Peter Higgs for the theoretical description of the Higgs mechanism in the year after the Higgs boson was found by CERN experiments.

Computer science

52. This NeXT Computer used by British scientist Sir Tim Berners-Lee at CERN became the first Web server.

53. CERN pioneered the introduction of TCP/IP for its intranet, beginning in 1984.

54. This played an influential role in the adoption of the TCP/IP in Europe (see History of the Internet and Protocol Wars).

55. In 1989, the World Wide Web was invented at CERN by Tim Berners-Lee.

56. Based on the concept of hypertext, the idea was designed to facilitate information sharing between researchers.

57. This stemmed from Berners-Lee's earlier work at CERN on a database named ENQUIRE.

58. A colleague, Robert Cailliau, became involved in 1990.

59. In 1995, Berners-Lee and Cailliau were jointly honoured by the Association for Computing Machinery for their contributions to the development of the World Wide Web.

60. A copy of the first webpage, created by Berners-Lee, is still published on the World Wide Web Consortium's website as a historical document.

61. The first website was activated in 1991.

62. On 30 April 1993, CERN announced that the World Wide Web would be free to anyone.

63. It became the dominant way through which most users interact with the Internet.

64. More recently, CERN has become a facility for the development of grid computing, hosting projects including the Enabling Grids for E-sciencE (EGEE) and LHC Computing Grid.

65. It also hosts the CERN Internet Exchange Point (CIXP), one of the two main internet exchange points in Switzerland.

66. As of 2022[update], CERN employs ten times more engineers and technicians than research physicists.

Particle accelerators

Current complex

67. CERN

68. Current particle and nuclear facilities

69. LHC | Accelerates protons and heavy ions

70. LEIR | Accelerates ions

71. SPS | Accelerates protons and ions

72. PSB | Accelerates protons

73. PS | Accelerates protons or ions

74. Linac 3 | Injects heavy ions into LEIR

75. Linac4 | Accelerates ions

76. AD | Decelerates antiprotons

77. ELENA | Decelerates antiprotons

78. ISOLDE | Produces radioactive ion beams

79. MEDICIS | Produces isotopes for medical purposes

80. A map of the Large Hadron Collider together with the Super Proton Synchrotron at CERN

81. CERN operates a network of seven accelerators and two decelerators, and some additional small accelerators.

82. Each machine in the chain increases the energy of particle beams before delivering them to experiments or to the next more powerful accelerator.

83. The decelerators naturally decrease the energy of particle beams before delivering them to experiments or further accelerators/decelerators.

84. Before an experiment is able to use the network of accelerators, it must be approved by the various Scientific Committees of CERN.

85. Currently (as of 2026) active machines are:

86. The LINAC 3 linear accelerator generating low energy particles.

87. It provides heavy ions at 4.2 MeV/Da for injection into the Low Energy Ion Ring (LEIR).

88. The Low Energy Ion Ring (LEIR) accelerates the ions from the ion linear accelerator LINAC 3, before transferring them to the Proton Synchrotron (PS).

89. This accelerator was commissioned in 2005, after having been reconfigured from the previous Low Energy Antiproton Ring (LEAR).

90. The Linac4 linear accelerator accelerates negative hydrogen ions to an energy of 160 MeV.

91. The ions are then injected to the Proton Synchrotron Booster (PSB) where both electrons are then stripped from each of the hydrogen ions and thus only the nucleus containing one proton remains.

92. The protons are then used in experiments or accelerated further in other CERN accelerators.

93. Linac4 serves as the source of all proton beams for CERN experiments.

94. The Proton Synchrotron Booster increases the energy of particles generated by the proton linear accelerator before they are transferred to the other accelerators.

95. The 28 GeV Proton Synchrotron (PS), built during 1954–1959 and still operating as a feeder to the more powerful SPS and to many of CERN's experiments.

96. The Super Proton Synchrotron (SPS), a circular accelerator with a diameter of 2 kilometres built in a tunnel, which started operation in 1976.

97. It was designed to deliver an energy of 300 GeV and was gradually upgraded to 450 GeV.

98. As well as having its own beamlines for fixed-target experiments (currently COMPASS and NA62), it has been operated as a proton–antiproton collider (the SppS collider), and for accelerating high energy electrons and positrons which were injected into the Large Electron–Positron Collider (LEP).

99. Since 2008, it has been used to inject protons and heavy ions into the Large Hadron Collider (LHC).

100. The On-Line Isotope Mass Separator (ISOLDE), which is used to study unstable nuclei.

101. The radioactive ions are produced by the impact of protons at an energy of 1.0–1.4 GeV from the Proton Synchrotron Booster.

102. It was first commissioned in 1967 and was rebuilt with major upgrades in 1974 and 1992.

103. The Antiproton Decelerator (AD), which reduces the velocity of antiprotons to about 10% of the speed of light for research of antimatter.

104. The AD machine was reconfigured from the previous Antiproton Collector (AC) machine.

105. The Extra Low Energy Antiproton ring (ELENA), which takes antiprotons from AD and decelerates them into low energies (speeds) for use in antimatter experiments.

106. The AWAKE experiment, which is a proof-of-principle plasma wakefield accelerator.

107. The CERN Linear Electron Accelerator for Research (CLEAR) accelerator research and development facility.

Large Hadron Collider

108. Many activities at CERN currently involve operating the Large Hadron Collider (LHC) and the experiments for it.

109. The LHC represents a large-scale, worldwide scientific cooperation project.

110. CMS detector for LHC

111. The LHC tunnel is located 100 metres underground, in the region between Geneva International Airport and the nearby Jura mountains.

112. The majority of its length is on the French side of the border.

113. It uses the 27 km circumference circular tunnel previously occupied by the Large Electron–Positron Collider (LEP), which was shut down in November 2000.

114. CERN's existing PS/SPS accelerator complexes are used to pre-accelerate protons and lead ions which are then injected into the LHC.

115. Eight experiments (CMS, ATLAS, LHCb, MoEDAL, TOTEM, LHCf, FASER and ALICE) are located along the collider; each of them studies particle collisions from a different aspect, and with different technologies.

116. Construction for these experiments required an extraordinary engineering effort.

117. For example, a special crane was rented from Belgium to lower pieces of the CMS detector into its cavern, since each piece weighed nearly 2000 tons.

118. The first of the approximately 5000 magnets necessary for construction was lowered down a special shaft at in March 2005.

119. The LHC has begun to generate vast quantities of data, which CERN streams to laboratories around the world for distributed processing, making use of a specialized grid infrastructure, the LHC Computing Grid.

120. In April 2005, a trial successfully streamed 600 MB/s to seven different sites across the world.

121. In August 2008, the initial particle beams were injected into the LHC.

122. The first beam was circulated through the entire LHC on 10 September 2008, but the system failed 10 days later because of a faulty magnet connection, and it was stopped for repairs on 19 September 2008.

123. The LHC resumed operation on 20 November 2009 by successfully circulating two beams, each with an energy of 3.5 teraelectronvolts (TeV).

124. The challenge for the engineers was then to line up the two beams so that they smashed into each other.

125. This is like "firing two needles across the Atlantic and getting them to hit each other" according to Stephen Myers, director for accelerators and technology.

126. On 30 March 2010, the LHC successfully collided two proton beams with 3.5 TeV of energy per proton, resulting in a 7 TeV collision energy.

127. This was enough to start the main research program, including the search for the Higgs boson.

128. When the 7 TeV experimental period ended, the LHC increased to 8 TeV (4 TeV per proton) starting March 2012, and soon began particle collisions at that energy.

129. In July 2012, CERN scientists announced the discovery of a new sub-atomic particle that was later confirmed to be the Higgs boson.

130. In March 2013, CERN announced that the measurements performed on the newly found particle allowed it to conclude that it was a Higgs boson.

131. In early 2013, the LHC was deactivated for a two-year maintenance period, to strengthen the electrical connections between magnets inside the accelerator and for other upgrades.

132. On 5 April 2015, after two years of maintenance and consolidation, the LHC restarted for a second run.

133. The first ramp to the record-breaking energy of 6.5 TeV was performed on 10 April 2015.

134. In 2016, the design collision rate was exceeded for the first time.

135. A second two-year period of shutdown begun at the end of 2018.

136. Following its final run on June 14 2026, the accelerator was switched off to begin CERN’s Long Shutdown 3 (LS3).

137. This programme will focus on maintenance and upgrades in preparation for the Laboratory for the High Luminosity Large Hadron Collider (HL-LHC), which is scheduled to be operational by the mid-2030s.

Accelerators under construction

138. As of October 2019, the construction is on-going to upgrade the LHC's luminosity in a project called High Luminosity LHC (HL–LHC).

139. This project should see the LHC accelerator upgraded by 2026 to an order of magnitude higher luminosity.

140. As part of the HL–LHC upgrade project, also other CERN accelerators and their subsystems are receiving upgrades.

141. Among other work, the LINAC 2 linear accelerator injector was decommissioned and replaced by a new injector accelerator, the LINAC4.

Decommissioned accelerators

142. The original linear accelerator LINAC 1.

143. Operated 1959–1992.

144. The LINAC 2 linear accelerator injector.

145. Accelerated protons to 50 MeV for injection into the Proton Synchrotron Booster (PSB).

146. Operated 1978–2018.

147. The 600 MeV Synchro-Cyclotron (SC) which started operation in 1957 and was shut down in 1991.

148. Was made into a public exhibition in 2012–2013.

149. The Intersecting Storage Rings (ISR), an early collider built from 1966 to 1971 and operated until 1984.

150. The Super Proton–Antiproton Synchrotron (SppS), operated 1981–1991.

151. A modification of Super Proton Synchrotron (SPS) to operate as a proton-antiproton collider.

152. The Large Electron–Positron Collider (LEP), which operated 1989–2000 and was the largest machine of its kind, housed in a 27 km-long circular tunnel which now houses the Large Hadron Collider.

153. The LEP Pre-Injector (LPI) accelerator complex, consisting of two accelerators, a linear accelerator called LEP Injector Linac (LIL; itself consisting of two back-to-back linear accelerators called LIL V and LIL W) and a circular accelerator called Electron Positron Accumulator (EPA).

154. The purpose of these accelerators was to inject positron and electron beams into the CERN accelerator complex (more precisely, to the Proton Synchrotron), to be delivered to LEP after many stages of acceleration.

155. Operational 1987–2001; after the shutdown of LEP and the completion of experiments that were directly fed by the LPI, the LPI facility was adapted to be used for the CLIC Test Facility 3 (CTF3).

156. The Low Energy Antiproton Ring (LEAR) was commissioned in 1982.

157. LEAR assembled the first pieces of true antimatter, in 1995, consisting of nine atoms of antihydrogen.

158. It was closed in 1996, and superseded by the Antiproton Decelerator.

159. The LEAR apparatus itself was reconfigured into the Low Energy Ion Ring (LEIR) ion booster.

160. The Antiproton Accumulator (AA), built 1979–1980, operations ended in 1997 and the machine was dismantled.

161. Stored antiprotons produced by the Proton Synchrotron (PS) for use in other experiments and accelerators (for example the ISR, SppS and LEAR).

162. For later half of its working life operated in tandem with Antiproton Collector (AC), to form the Antiproton Accumulation Complex (AAC).

163. The Antiproton Collector (AC), built 1986–1987, operations ended in 1997 and the machine was converted into the Antiproton Decelerator (AD), which is the successor machine for Low Energy Antiproton Ring (LEAR).

164. Operated in tandem with Antiproton Accumulator (AA) and the pair formed the Antiproton Accumulation Complex (AAC), whose purpose was to store antiprotons produced by the Proton Synchrotron (PS) for use in other experiments and accelerators, like the Low Energy Antiproton Ring (LEAR) and Super Proton–Antiproton Synchrotron (SppS).

165. The Compact Linear Collider Test Facility 3 (CTF3), which studied feasibility for the future normal conducting linear collider project (the CLIC collider).

166. In operation 2001–2016.

167. One of its beamlines has been converted, from 2017 on, into the new CERN Linear Electron Accelerator for Research (CLEAR) facility.

Possible future accelerators

168. CERN, in collaboration with groups worldwide, is investigating two main concepts for future accelerators: A linear electron-positron collider with a new acceleration concept to increase the energy (CLIC) and a larger version of the LHC, a project currently named Future Circular Collider.

Sites

169. This section does not cite any sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. (December 2023) (Learn how and when to remove this message)

170. The smaller accelerators are on the main Meyrin site, also known as the West Area, which was originally built in Switzerland alongside the French border, but has been extended to span the border since 1965.

171. The French side is under Swiss jurisdiction and there is no obvious border within the site, apart from a line of marker stones.

172. The SPS and LEP/LHC tunnels are almost entirely outside the main site, and are mostly buried under French farmland and invisible from the surface.

173. They have surface sites at points around them, either as the location of buildings associated with experiments or other facilities needed to operate the colliders such as cryogenic plants and access shafts.

174. The experiments are located at the same underground level as the tunnels at these sites.

175. Three of these experimental sites are in France, with ATLAS in Switzerland, and some of the ancillary cryogenic and access sites are in Switzerland.

176. The largest of the experimental sites is the Prévessin site, also known as the North Area, which is the target station for non-collider experiments on the SPS accelerator.

177. Other sites are the ones which were used for the UA1, UA2 and the LEP experiments.

178. The latter are used by LHC experiments.

179. Outside of the LEP and LHC experiments, most are officially named and numbered after the site where they were located.

180. For example, NA32 was an experiment looking at the production of so-called "charmed" particles and located at the Prévessin (North Area) site.

181. WA22 used the Big European Bubble Chamber (BEBC) at the Meyrin (West Area) site to examine neutrino interactions.

182. The UA1 and UA2 experiments were considered to be in the Underground Area, i.e. situated underground at sites on the SPS accelerator.

183. Most of the roads on the CERN Meyrin and Prévessin sites are named after famous physicists, such as Niels Bohr, who pushed for CERN's creation.

184. Other notable names are Richard Feynman, Albert Einstein, and Wolfgang Pauli.

185. CERN Building 40 at the Meyrin site

186. Interior view of Building 40, home to offices for scientists working on the CMS and ATLAS collaborations.

187. CERN Data Centre

188. Antimatter Factory

189. Elena Antimatter Generator

Participation and funding

Member states and budget

190. Since its foundation by 12 members in 1954, CERN regularly accepted new members.

191. All new members have remained in the organization continuously since their accession, except Spain and Yugoslavia.

192. Spain first joined CERN in 1961, withdrew in 1969, and rejoined in 1983.

193. Yugoslavia was a founding member of CERN but quit in 1961.

194. Of the 24 members, Israel joined CERN as a full member in January 2014, becoming the first, and currently only, non-geographically European full member.

195. The budget contributions of member states are computed based on their Net National Income at factor cost.

196. Member state | Status since | Contribution(million CHF for 2026) | Contribution(fraction of Member state contributions for 2026) | Contribution per capita(CHF/person for 2026)

197. Founding Members

198. Belgium | 29 September 1954 | 34.70 | 2.12% | 2.9

199. Denmark | 29 September 1954 | 23.06 | 1.87% | 3.9

200. France | 29 September 1954 | 159.73 | 12.96% | 2.3

201. Germany | 29 September 1954 | 251.87 | 20.44% | 3.0

202. Greece | 29 September 1954 | 12.41 | 1.00% | 1.2

203. Italy | 29 September 1954 | 118.77 | 9.64% | 2.0

204. Netherlands | 29 September 1954 | 62.35 | 5.06% | 3.4

205. Norway | 29 September 1954 | 30.91 | 2.51% | 5.6

206. Sweden | 29 September 1954 | 31.06 | 2.52% | 2.9

207. Switzerland | 29 September 1954 | 46.51 | 3.77% | 5.2

208. United Kingdom | 29 September 1954 | 185.73 | 15.07% | 2.7

209. Yugoslavia | 29 September 1954 | 0 | 0% | 0.0

210. Acceded Members

211. Austria | 1 June 1959 | 26.10 | 2.12% | 2.9

212. Spain | 1 January 1983 | 86.43 | 7.01% | 1.8

213. Portugal | 1 January 1986 | 13.59 | 1.10% | 1.3

214. Finland | 1 January 1991 | 15.24 | 1.24% | 2.7

215. Poland | 1 July 1991 | 40.80 | 3.31% | 1.1

216. Hungary | 1 July 1992 | 9.36 | 0.76% | 1.0

217. Czech Republic | 1 July 1993 | 16.10 | 1.31% | 1.5

218. Slovakia | 1 July 1993 | 6.53 | 0.53% | 1.2

219. Bulgaria | 11 June 1999 | 5.16 | 0.42% | 0.8

220. Israel | 6 January 2014 | 28.77 | 2.33% | 2.9

221. Romania | 17 July 2016 | 17.61 | 1.43% | 0.9

222. Serbia | 24 March 2019 | 3.91 | 0.32% | 0.6

223. Estonia | 30 August 2024 | 2.07 | 0.17% | 1.5

224. Slovenia | 21 June 2025 | 3.38 | 0.27% | 1.6

225. Associate Members in the pre-stage to membership

226. Cyprus | 1 April 2016 | 1.15 | 0.09% | 1.3

227. Associate Members

228. Turkey | 6 May 2015 | 5.44 | 0.89% | 0.05

229. Pakistan | 31 July 2015 | 2.01 | 0.16% | 0.01

230. Ukraine | 5 October 2016 | 1.02 | 0.08% | 0.03

231. India | 16 January 2017 | 18.91 | 1.53% | 0.01

232. Lithuania | 8 January 2018 | 1.00 | 0.08% | 0.35

233. Croatia | 10 October 2019 | 1.00 | 0.08% | 0.26

234. Latvia | 2 August 2021 | 1.07 | 0.09% | 0.6

235. Brazil | 13 March 2024 | 10.95 | 0.89% | 0.05

236. Ireland | 22 October 2025 | 1.77 | 0.14% | 0.33

237. Chile | 2 April 2026

238. Total Members, Candidates and Associates | 1,276.47 | 103.6% | N/A

239. Maps of the history of CERN membership

240. 1954 (12 members): CERN is founded (1954–1990 borders) 1959 (13 members): Austria joins (1954–1990 borders) 1961 (13 members): Spain joins and Yugoslavia leaves (1954–1990 borders) 1969 (12 members): Spain leaves (1954–1990 borders) 1983 (13 members): Spain re-joins (1954–1990 borders) 1985 (14 members): Portugal joins (1954–1990 borders) 1991 (16 members): Poland and Finland join, and Germany has been reunified (post-1993 borders) 1992 (17 members): Hungary joins (post-1993 borders) 1993 (19 members): Czech Republic and Slovakia join (post-1993 borders) 1999 (20 members): Bulgaria joins (post-1993 borders) Animated map showing changes in CERN membership from 1954 until 1999 (borders are as at dates of change)

Enlargement

241. Associate Members, Candidates:

242. Turkey signed an association agreement on 12 May 2014 and became an associate member on 6 May 2015.

243. Pakistan signed an association agreement on 19 December 2014 and became an associate member on 31 July 2015.

244. Cyprus signed an association agreement on 5 October 2012 and became an associate member in the pre-stage to membership on 1 April 2016.

245. Ukraine signed an association agreement on 3 October 2013.

246. The agreement was ratified on 5 October 2016.

247. India signed an association agreement on 21 November 2016.

248. The agreement was ratified on 16 January 2017.

249. Slovenia was approved for admission as an Associate Member state in the pre-stage to membership on 16 December 2016.

250. The agreement was ratified on 4 July 2017.

251. Lithuania was approved for admission as an Associate Member state on 16 June 2017.

252. The association agreement was signed on 27 June 2017 and ratified on 8 January 2018.

253. Croatia was approved for admission as an Associate Member state on 28 February 2019.

254. The agreement was ratified on 10 October 2019.

255. Latvia and CERN signed an associate membership agreement on 14 April 2021.

256. Latvia was formally admitted as an Associate Member on 2 August 2021.

257. Brazil became the first associate member of the Americas on 13 March 2024, after signing the associate membership agreement in March 2022.

258. Chile and Ireland were approved as new Associate Member States in March 2025.

259. Ireland was admitted on 22 October 2025.

260. Chile officially became an associate member state on 2 April 2026.

International relations

261. Three countries have observer status:

262. Japan – since 1995

263. Russia – since 1993 (suspended as of March 2022)

264. United States – since 1997

265. Also observers are the following international organizations:

266. UNESCO – since 1954

267. European Commission – since 1985

268. JINR – since 2014 (suspended as of March 2022)

269. Non-Member States (with dates of Co-operation Agreements) currently involved in CERN programmes are:

270. Albania – October 2014

271. Algeria – 2008

272. Argentina – 11 March 1992

273. Armenia – 25 March 1994

274. Australia – 1 November 1991

275. Azerbaijan – 3 December 1997

276. Bangladesh – 2014

277. Belarus – 28 June 1994 (suspended as of March 2022)

278. Bolivia – 2007

279. Bosnia & Herzegovina – 16 February 2021

280. Canada – 11 October 1996

281. China – 12 July 1991, 14 August 1997 & 17 February 2004

282. Colombia – 15 May 1993

283. Costa Rica – February 2014

284. Ecuador – 1999

285. Egypt – 16 January 2006

286. Georgia – 11 October 1996

287. Iceland – 11 September 1996

288. Iran – 5 July 2001

289. Jordan – 12 June 2003 MoU with Jordan and SESAME, in preparation of a cooperation agreement signed in 2004.

290. Kazakhstan – June 2018

291. Lebanon – 2015

292. Malta – 10 January 2008

293. Mexico – 20 February 1998

294. Mongolia – 2014

295. Montenegro – 12 October 1990

296. Morocco – 14 April 1997

297. Nepal – 19 September 2017

298. New Zealand – 4 December 2003

299. North Macedonia – 27 April 2009

300. Palestine – December 2015

301. Paraguay – January 2019

302. Peru – 23 February 1993

303. Philippines – 2018

304. Qatar – 2016

305. Republic of Korea (South Korea) – 25 October 2006

306. Saudi Arabia – 2006

307. South Africa – 4 July 1992

308. Sri Lanka – February 2017

309. Thailand – 2018

310. Tunisia – May 2014

311. United Arab Emirates – 2006

312. Vietnam – 2008

313. CERN also has scientific contacts with the following other countries and regions:

314. Bahrain

315. Cuba

316. Ghana

317. Honduras

318. Hong Kong

319. Indonesia

320. Kuwait

321. Luxemburg

322. Madagascar

323. Malaysia

324. Mauritius

325. Morocco

326. Mozambique

327. Oman

328. Rwanda

329. Singapore

330. Sudan

331. Taiwan

332. Tanzania

333. Uzbekistan

334. Zambia

335. International research institutions, such as CERN, can aid in science diplomacy.

Associated institutions

336. ESO and CERN have a cooperation agreement.

337. A large number of institutes around the world are associated to CERN through current collaboration agreements and/or historical links.

338. The list below contains organizations represented as observers to the CERN Council, organizations to which CERN is an observer and organizations based on the CERN model:

339. European Molecular Biology Laboratory, organization based on the CERN model

340. European Space Research Organisation (since 1975 ESA), organization based on the CERN model

341. European Southern Observatory, organization based on the CERN model.

342. Also, the two organisations share a pension fund for their employees.

343. JINR, observer to CERN Council, CERN is represented in the JINR Council.

344. JINR is currently suspended, due to the CERN Council Resolution of 25 March 2022.

345. SESAME, CERN is an observer to the SESAME Council

346. UNESCO, observer to CERN Council

.cern

347. .cern

348. Introduced | August 13, 2014; 12 years ago (2014-08-13)

349. TLD type | Generic top-level domain

350. Status | Active

351. Registry | IANA

352. Intended use | Domains related to the European Organization for Nuclear Research

353. Actual use | Domains related to the European Organization for Nuclear Research

354. Registration restrictions | Domain registrations only possible by CERN

355. .cern is a top-level domain for CERN.

356. It was registered on 13 August 2014.

357. On 20 October 2015, CERN moved its main website to home.cern.

Open science

358. The Open Science movement focuses on making scientific research openly accessible and on creating knowledge through open tools and processes.

359. Open access, open data, open source software and hardware, open licenses, digital preservation and reproducible research are primary components of open science and areas in which CERN has been working towards since its formation.

360. Since the late 1950s, the CERN Scientific Information Service was involved in distributing preprints.

361. Notably, the librarian Luisella Goldschmidt-Clermont played an important role in transforming the existing culture of personal sharing of research results into a more institutional approach and therefore lying the groundwork for what has only later been called open science.

362. CERN has developed policies and official documents that enable and promote open science, starting with CERN's founding convention in 1953 which indicated that all its results are to be published or made generally available.

363. Since then, CERN published its open access policy in 2014, which ensures that all publications by CERN authors will be published with gold open access and most recently an open data policy that was endorsed by the four main LHC collaborations (ALICE, ATLAS, CMS and LHCb).

364. The open data policy complements the open access policy, addressing the public release of scientific data collected by LHC experiments after a suitable embargo period.

365. Prior to this open data policy, guidelines for data preservation, access and reuse were implemented by each collaboration individually through their own policies which are updated when necessary.

366. The European Strategy for Particle Physics, a document mandated by the CERN Council that forms the cornerstone of Europe's decision-making for the future of particle physics, was last updated in 2020 and affirmed the organisation's role within the open science landscape by stating: "The particle physics community should work with the relevant authorities to help shape the emerging consensus on open science to be adopted for publicly-funded research, and should then implement a policy of open science for the field".

367. Beyond the policy level, CERN has established a variety of services and tools to enable and guide open science at CERN, and in particle physics more generally.

368. On the publishing side, CERN has initiated and operates a global cooperative project, the Sponsoring Consortium for Open Access Publishing in Particle Physics, SCOAP3, to convert scientific articles in high-energy physics to open access.

369. In 2018, the SCOAP3 partnership represented 3,000+ libraries from 44 countries and 3 intergovernmental organizations who have worked collectively to convert research articles in high-energy physics across 11 leading journals in the discipline to open access.

370. Public-facing results can be served by various CERN-based services depending on their use case: the CERN Open Data portal, Zenodo, the CERN Document Server, INSPIRE and HEPData are the core services used by the researchers and community at CERN, as well as the wider high-energy physics community for the publication of their documents, data, software, multimedia, etc. CERN's efforts towards preservation and reproducible research are best represented by a suite of services addressing the entire physics analysis lifecycle, such as data, software and computing environment.

371. CERN Analysis Preservation helps researchers to preserve and document the various components of their physics analyses.

372. REANA (Reusable Analyses) enables the instantiating of preserved research data analyses on the cloud.

373. All services are built using open source software and strive towards compliance with best effort principles, such as the FAIR principles, the FORCE11 guidelines and Plan S, while taking into account relevant activities carried out by the European Commission.

Public exhibitions

374. The Globe of Science and Innovation at CERN

375. The first public exhibition at CERN was the Microcosm museum which hosted an exhibition about particle physics and CERN history.

376. It closed permanently on 18 September 2022, in preparation for the installation of the exhibitions in the newly built science center CERN Science Gateway.

377. The CERN Science Gateway, constructed by the Renzo Piano building workshop was opened in October 2023.

378. It is home to the following spaces:

379. Three permanent hands-on exhibitions Discover CERN, which hosts exhibits to explain how particles are accelerated in CERN's particle accelerators and detected in the large experiments.

380. This exhibition hosts a fully functioning 2 MeV proton accelerator named Experimental Linac for Surface Analysis (ELISA).

381. Our Universe, which hosts two distinct exhibitions: One part (Back to the Big Bang) explains the scientific questions which are explored by experiments in particle physics and cosmology.

382. Another part (Exploring the unknown) hosts an art exhibition which is on display from October 2023 to October 2026.

383. Quantum World focuses on explaining concepts from Quantum Mechanics, such as entanglement, uncertainty, or virtual particles.

384. An auditorium with up to 800 seats.

385. 2 Education Labs hosting hands-on workshops for school groups and walk-in visitors.

386. The Globe of Science and Innovation, which opened in late 2005, is open to the public.

387. It is used four times a week for special exhibits.

388. CERN also provides daily tours to certain facilities such as the Synchro-cyclotron (CERNs first particle accelerator) and the superconducting magnet workshop.

Arts at CERN

389. CERN launched its Cultural Policy for engaging with the arts in 2011.

390. The initiative provided the essential framework and foundations for establishing Arts at CERN, the arts programme of the Laboratory.

391. Since 2012, Arts at CERN has fostered creative dialogue between art and physics through residencies, art commissions, exhibitions and events.

392. Artists across all creative disciplines have been invited to CERN to experience how fundamental science pursues the big questions about our universe.

393. Even before the arts programme officially started, several highly regarded artists visited the laboratory, drawn to physics and fundamental science.

394. In 1972, James Lee Byars was the first artist to visit the laboratory and the only one, so far, to feature on the cover of the CERN Courier.

395. Mariko Mori, Gianni Motti [fr], Cerith Wyn Evans, John Berger and Anselm Kiefer are among the artists who came to CERN in the years that followed.

396. The programmes of Arts at CERN are structured according to their values and vision to create bridges between cultures.

397. Each programme is designed and formed in collaboration with cultural institutions, other partner laboratories, countries, cities and artistic communities eager to connect with CERN's research, support their activities, and contribute to a global network of art and science.

398. They comprise research-led artistic residencies that take place on-site or remotely.

399. More than 200 artists from 80 countries have participated in the residencies to expand their creative practices at the Laboratory, benefiting from the involvement of 400 physicists, engineers and CERN staff.

400. Between 500 and 800 applications are received every year.

401. The programmes comprise Collide, the international residency programme organised in partnership with a city; Connect, a programme of residencies to foster experimentation in art and science at CERN and in scientific organisations worldwide in collaboration with Pro Helvetia, and Guest Artists, a short stay for artists to stay to engage with CERN's research and community.

In popular culture

402. The statue of Shiva engaging in the Nataraja dance (symbolising his cosmic dance of creation and destruction) presented by the Department of Atomic Energy of India

403. Geneva tram 18 at CERN

404. The band Les Horribles Cernettes was founded by women from CERN.

405. The name was chosen so to have the same initials as the LHC.

406. The science journalist Katherine McAlpine made a rap video called "Large Hadron Rap" about CERN's Large Hadron Collider with some of the facility's staff.

407. Particle Fever, a 2013 documentary, explores CERN throughout the inside and depicts the events surrounding the 2012 discovery of the Higgs Boson.

408. John Titor, a self-proclaimed time traveler, alleged that CERN would invent time travel in 2001.

409. CERN is depicted in the visual novel/anime series Steins;Gate as SERN, a shadowy organization that has been researching time travel in order to restructure and control the world.

410. In Robert J. Sawyer's 1999 science fiction novel Flashforward, as CERN's Large Hadron Collider accelerator is performing a run to search for the Higgs boson the entire human race sees themselves twenty-one years and six months in the future.

411. A number of conspiracy theories feature CERN, accusing the organization of partaking in occult rituals and secret experiments involving opening portals into Hell or other dimensions, shifting the world into an alternative timeline and causing earthquakes.

412. In Dan Brown's 2000 mystery-thriller novel Angels & Demons and 2009 film of the same name, a canister of antimatter is stolen from CERN.

413. CERN is depicted in a 2009 episode of South Park (Season 13, Episode 6), "Pinewood Derby".

414. Randy Marsh, the father of one of the main characters, breaks into the "Hadron Particle Super Collider in Switzerland" and steals a "superconducting bending magnet created for use in tests with particle acceleration" to use in his son Stan's Pinewood Derby racer.

415. In the 2010 season 3 episode 15 of the TV situation comedy The Big Bang Theory, "The Large Hadron Collision", Leonard and Raj travel to CERN to attend a conference and see the LHC.

416. The 2012 student film Decay, which centres on the idea of the Large Hadron Collider transforming people into zombies, was filmed on location in CERN's maintenance tunnels.

417. The Compact Muon Solenoid at CERN was used as the basis for the Megadeth's Super Collider album cover.

418. CERN forms part of the back story of the massively multiplayer augmented reality game Ingress, and in the 2018 Japanese anime television series Ingress: The Animation, based on Niantic's augmented reality mobile game of the same name.

419. In 2015, Sarah Charley, US communications manager for LHC experiments at CERN with graduate students Jesse Heilman of the University of California, Riverside, and Tom Perry and Laser Seymour Kaplan of the University of Wisconsin, Madison created a parody video based on "Collide", a song by American artist Howie Day.

420. The lyrics were changed to be from the perspective of a proton in the Large Hadron Collider.

421. After seeing the parody, Day re-recorded the song with the new lyrics, and released a new version of "Collide" in February 2017 with a video created during his visit to CERN.

422. In 2015, Ryoji Ikeda created an art installation called "Supersymmetry" based on his experience as a resident artist at CERN.

423. In the 2017 season 10 episode 6 of the British science fiction Doctor Who, "Extremis", CERN is one of several locations found to be connected by a hub of mysterious portals.

424. The television series Mr. Robot features a secretive, underground project apparatus that resembles the ATLAS experiment.

425. Parallels, a Disney+ television series released in March 2022, includes a particle-physics laboratory at the French-Swiss border called "ERN".

426. Various accelerators and facilities at CERN are referenced during the show, including ATLAS, CMS, the Antiproton Decelerator, and the FCC.

427. In 2004, a two-metre statue of the Nataraja, the dancing form of the Hindu god Shiva, was unveiled at CERN.

428. The statue, symbolizing Shiva's cosmic dance of creation and destruction, was presented by the Indian government to celebrate the research center's long association with India.

429. A special plaque next to the statue explains the metaphor of Shiva's cosmic dance with quotations from physicist Fritjof Capra:Hundreds of years ago, Indian artists created visual images of dancing Shivas in a beautiful series of bronzes.

430. In our time, physicists have used the most advanced technology to portray the patterns of the cosmic dance.

431. The metaphor of the cosmic dance thus unifies ancient mythology, religious art and modern physics.