Groupe Bull
A French computing company with roots in punched-card machines and a modern focus on enterprise computing, cybersecurity and high-performance systems.
Last updated October 14, 2026
AI crawler reads
No AI crawler has read this profile since Oct 28, 2026.
Overview
Groupe Bull, commonly known as Bull, is a French computing company whose history extends from punched-card data-processing equipment to mainframes, servers, supercomputers, secure communications and large-scale information-technology services. The business was created in 1931 as H.W. Egli-Bull, drawing on patents developed by Norwegian engineer Fredrik Rosing Bull for machines that sorted, recorded and tabulated information stored on punched cards. After a 1933 reorganization, it became Compagnie des Machines Bull, establishing the corporate identity that later evolved into Groupe Bull and Bull Information Systems. Bull developed during the period when European governments and large enterprises were adopting mechanized data processing. Its products served insurance companies, banks, public administrations and other organizations that needed to manage large volumes of structured records. As electronic computing replaced electromechanical tabulation, Bull moved into computers and mainframes and became an important French participant in the European computing industry. Its corporate form and ownership changed repeatedly as it sought access to technology, capital and international distribution networks. In 1964, Bull entered a joint venture with General Electric, partly to preserve French participation in the expanding mainframe market. General Electric acquired Bull-GE in 1970, after which the operation became Honeywell-Bull. In 1975, Honeywell-Bull combined with Compagnie Internationale pour l'Informatique, creating CII Honeywell-Bull. The French government nationalized the business in 1982, reflecting the strategic importance that France attached to domestic computing capabilities. A later Honeywell-NEC joint venture used the Honeywell-Bull name in 1987; after Bull became the majority shareholder, the business was renamed Bull HN Information Systems in 1989. Bull also pursued international expansion. In December 1989, it acquired Zenith Electronics' data-processing activities, including Zenith Data Systems, and retained operations in the United States. The French government subsequently began privatizing Bull in 1993, with the re-privatization process completed during 1995–1997. Through the following decades, the company supplied enterprise hardware and software, mainframes, Unix servers, high-performance computing platforms, data-center infrastructure and related consulting and integration services. Its customer base included defense, finance, healthcare, manufacturing, telecommunications and public-sector organizations. A significant later product was the Hoox range of secure mobile devices. Bull presented the Hoox m2 in 2014 as a European smartphone designed with integrated security features for protected voice, messaging, email and data communications. French cybersecurity authorities approved the device for use with information classified as Restricted Information, giving Bull a distinctive position at the intersection of mobile communications, defense and government security. Bull's history also includes controversy. Its subsidiary Amesys supplied the Eagle internet-monitoring system to Libya in 2007. Human-rights groups and press-freedom organizations alleged that the system enabled the government of Muammar Gaddafi to monitor citizens, dissidents and foreign journalists. Reporters Without Borders listed Amesys among companies it criticized as corporate enablers of online repression, while a French judicial inquiry examined allegations relating to complicity in torture. Bull sold the Eagle business to Nexa Technologies in 2012. In 2014, Atos announced a tender offer for Bull and acquired a controlling stake, later moving toward full ownership. Bull subsequently became associated with Atos's advanced-computing activities. Atos announced in 2022 that its activities would be reorganized, with Bull positioned within Eviden, the consulting, digital, data and cybersecurity business. The attempted separation or sale of E…
History
Bull's origins lie in the work of Fredrik Rosing Bull, a Norwegian engineer who patented a combined punched-card sorter, recorder and tabulator in 1919. The technology was first used by Storebrand, the Norwegian insurance company that had supported Bull's work, and later by the Danish insurer Hafnia. After Bull died in 1925, his collaborators Reidar Knutsen and Kurt Andréas Knutsen continued the technical and commercial development of the machines. As demand grew, outside investors helped establish H.W. Egli-Bull in 1931. Additional investment led to a reorganization in 1933 and the adoption of the name Compagnie des Machines Bull. The company built its early business around mechanized information processing for insurers and other large organizations, then adapted as electronic computers began to replace punched-card equipment. Bull's postwar development was shaped by partnerships and changes in ownership. In 1964, it created Bull-General Electric, a joint venture intended in part to maintain French involvement in the mainframe industry. General Electric acquired the operation in 1970 and renamed it Honeywell-Bull. In 1975, Honeywell-Bull merged with Compagnie Internationale pour l'Informatique, becoming CII Honeywell-Bull. The French government nationalized the combined business in 1982, treating computing as a strategic industrial sector. A further joint venture involving nationalized Bull, Honeywell Information Systems and NEC revived the Honeywell-Bull name in 1987. When Bull became the majority shareholder, the operation was renamed Bull HN Information Systems in February 1989. In December of that year, Bull acquired Zenith Electronics' data-systems operations. Zenith Data Systems provided Bull with additional manufacturing, sales and distribution resources in the United States, including facilities and headquarters that were retained for a period. France began privatizing Bull in 1993, and the process was completed between 1995 and 1997. As an independent or semi-independent enterprise, Bull continued to focus on enterprise computing, mainframes, Unix servers, high-performance computing and services for government and regulated industries. The company developed or supplied systems such as GCOS mainframes, Escala servers and later BullSequana high-performance platforms. It also participated in cloud infrastructure, modular data centers, networking, systems integration and enterprise software services. Bull's security activities became particularly visible through the Hoox secure-mobile product family. The Hoox m2, introduced in 2014, was designed to secure voice calls, text messages, email and data. Its approval by the French national information-systems security agency for use with Restricted Information strengthened Bull's association with government and defense-grade communications. The same period brought reputational and legal controversy involving Amesys, a Bull subsidiary focused on defense and aerospace systems and software. Amesys sold its Eagle internet-monitoring system to Libya in 2007. The system was subsequently associated with surveillance of Libyan citizens and foreign journalists under Muammar Gaddafi. Reporters Without Borders criticized Amesys as a corporate actor enabling digital repression, while the International Federation for Human Rights brought allegations that contributed to a French judicial inquiry into possible complicity in torture. In March 2012, Bull sold the Eagle activity to Nexa Technologies for a reported €4 million, according to the cited reference material. Atos announced a tender offer for Bull in 2014 and acquired a controlling interest in August of that year. Bull was then absorbed into Atos's advanced-computing organization, although the Bull name continued to identify important high-performance-computing and secure-technology offerings. In 2022, Atos proposed dividing its activities between separate businesses, with Bull associated with Eviden. The planned separation and possible disposal of Eviden encountered difficulties, leaving the business connected to Atos. The supplied reference material further reports that the French state completed an acquisition of strategic Atos assets, including Bull, on March 31, 2026. This latest ownership event should be checked against current corporate filings before being treated as settled historical fact.
- 2026
French state ownership is reported
[1]The supplied reference material reports completion of a transaction transferring strategic Atos assets, including Bull, to the French state on March 31, 2026; the ownership status should be verified against current official records.
- 2022
Bull is associated with Atos's Eviden business
[1]Atos announced a proposed organizational split that placed Bull within Eviden.
- 2014
Atos acquires control of Bull
[1]Atos acquired a controlling stake through a tender offer and incorporated Bull's capabilities into its advanced-computing activities.
- 2012
Eagle System business is sold
[1]Bull divested the Eagle monitoring-system activity of Amesys to Nexa Technologies.
- 1997
Re-privatization is completed
[1]The privatization process initiated in 1993 was completed during the 1995–1997 period.
- 1993
Privatization process begins
[1]The French government began the process of returning Bull to private ownership.
- 1989
Bull acquires Zenith Data Systems
[1]Bull purchased Zenith Electronics' data-processing activities and retained significant United States operations.
- 1982
The French state nationalizes the business
[1]The French government nationalized the computing business as part of a strategy to retain domestic capabilities in a strategically important industry.
- 1975
CII Honeywell-Bull is formed
[1]Honeywell-Bull merged with Compagnie Internationale pour l'Informatique.
- 1970
General Electric acquires Bull-GE
[1]General Electric acquired the joint venture, which was subsequently renamed Honeywell-Bull.
Products and positioning
French and European enterprise technology provider emphasizing mission-critical computing, high-performance computing, sovereign and secure infrastructure, public-sector systems, and specialized services for regulated industries.
Mainframe computers
GCOS mainframes
Bull's GCOS family represents its long-running mainframe business. These systems were designed for mission-critical transaction processing and large-scale workloads in government, finance and other organizations requiring centralized computing, reliability and long-term software compatibility.
Unix enterprise servers
Escala servers
Escala systems were enterprise servers associated with Bull's Unix and AIX activities. They targeted organizations needing dependable midrange and large-scale computing for databases, business applications and other workloads traditionally handled by proprietary enterprise systems.
High-performance computing
BullSequana
BullSequana is a family of high-performance computing and data-center systems associated with Bull's advanced-computing portfolio. The systems are intended for scientific, industrial, public-sector and other workloads requiring substantial processing capacity, scalable infrastructure and specialized computing expertise.
Secure mobile communications · 2014
Hoox secure smartphones
Hoox smartphones were designed for protected professional and government communications. The range emphasized confidentiality for voice calls, SMS, email and data, and the Hoox m2 received French approval for use with information classified as Restricted Information.
Network monitoring and intelligence software
Amesys Eagle System
The Eagle System was an internet-monitoring platform developed by Amesys for governmental and security applications. It became internationally controversial after reports linked its deployment in Libya to surveillance of citizens, dissidents and journalists. Bull divested the activity in 2012.
Controversies
2011
Amesys and Libya surveillance controversy
Amesys, a Bull subsidiary, faced international criticism after reports said that its Eagle internet-monitoring technology had been sold to the government of Muammar Gaddafi in 2007 and used to monitor citizens and foreign journalists. Reporters Without Borders identified Amesys as a company associated with enabling online repression, while a French judicial inquiry followed allegations concerning possible complicity in torture.
Brand decisions
2022
Place Bull within EvidenStrategyBackground
Atos announced a proposed separation of its activities into distinct business areas.
Action taken
Bull's advanced-computing activities were positioned within Eviden, alongside consulting, data, digital and cybersecurity operations.
Aftermath
The planned sale or flotation of Eviden did not proceed as initially intended, leaving Bull connected to the broader Atos group according to the supplied reference material.
2014
Accept Atos controlM&ABackground
Bull was seeking a stronger position and resources in advanced computing and enterprise technology services.
Action taken
Atos launched a tender offer and acquired a controlling stake in Bull, with plans to acquire the remaining interests.
Aftermath
Bull became part of Atos's advanced-computing business and later became associated with Eviden.
2014
Launch the Hoox m2Product launchBackground
Government, defense and regulated customers required stronger protection for mobile voice and data communications.
Action taken
Bull launched the Hoox m2 secure smartphone and promoted integrated protection for calls, messages, email and data.
Aftermath
The product received French approval for use with Restricted Information, reinforcing Bull's security-oriented positioning.
2012
Divest the Eagle SystemM&ABackground
Amesys's sale of monitoring technology to Libya generated human-rights criticism and legal scrutiny.
Action taken
Bull sold the Eagle System activity to Nexa Technologies.
Aftermath
The divestment separated Bull from the specific monitoring product, although the controversy remained associated with the group's corporate history.
Reported sale price. €4 million (March 2012)
1989
Acquire Zenith Data SystemsM&ABackground
Bull sought broader international reach and additional capabilities in data-processing systems.
Action taken
Bull acquired Zenith Electronics' data-systems operations, including Zenith Data Systems.
Aftermath
Bull retained Zenith-related headquarters and manufacturing operations in the United States for a period.
1982
Nationalization by the French governmentStrategyBackground
France regarded computing as a strategic industrial capability and sought greater national control over the sector.
Action taken
The French state nationalized the Bull-related business.
Aftermath
Bull continued operating under state ownership until privatization began in 1993 and was completed during 1995–1997.
1964
Form a General Electric joint ventureStrategyBackground
Bull needed technological and commercial scale as electronic mainframe computing developed and international competition intensified.
Action taken
Bull created Bull-General Electric with General Electric, while seeking to preserve a French position in the mainframe sector.
Aftermath
General Electric acquired Bull-GE in 1970, leading to the Honeywell-Bull phase of the company's history.
Sources2 sources
Cite this profile: Cite the canonical profile. /brand-wiki/groupe-bull · Editorial policy · How profiles are compiled