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Gretag, or Gretacoder Data Systems, or simply Gretacoder, was a manufacturer of cryptographic equipment, based in Regensdorf near Zürich (Switzerland). It was founded by Dr. Edgar Gretener who was not only a direct competitor of Boris Hagelin, but also worked with him on a number of occasions. The company, who also made the encryption devices for international SWIFT bank transactions, had a world-wide customer base and had once over 2500 people on its payroll.
Gretag company logo

Over the years, Gretag produced a range of commercial, industrial and military cipher machines. The company changed hands several times and was eventually split up into different companies. In 2004, the crypto-part was dissolved when it was owned by SafeNet. By that time however, most of its patents had already been transferred to Omnisec, who are still in business today.

 Gretag cipher machines

1943: Dr. Edgar Gretener AG
Gretag AG started life around 1943, when its founder, Dr. Edgar Gretener established Dr. Edgar Gretener AG in Zürich (Switzerland). Gretener was one of the inventors of the famous Eidophor large screen video projector that was marketed by his company. He would later become famous for a series of hi-tech cipher machines and for his wide range of colour image processing equipment for the printing industry. All equipment manufactured in the early years carried the name of the founder: Dr. Edgar Gretener AG.

1946: Cipher Machines
In 1946, the company started the development of teleprinters (telex) and cipher machines. In 1947, a small lightweight teleprinter, called the ETK-47, was succesfully introduced and it wasn't before long that it became widely accepted by the Swiss Army and by small businesses. In 1949, the Swiss Army expressed an interest in online cipher machines, resulting in a co-operation between Dr. Edgar Gretener and competitor Boris Hagelin, another Swiss crypto developer.

The result of this joint development was the so-called Telekrypto-Gerät 35, also referred to as the GR tg 35, TKG or TC-35 [8]. In 1951, 35 of these TKG machines were delivered to the Danish Army [9]. The machine formed the basis for the development of later cipher machines such as the TC-53 that was designed to work with Gretener's proprietary ETK-47 teleprinter.

Apart from Dr. Edgar Gretener himself, the key developer of the cipher systems was Kurt Ehrat who had joined the company on 1 April 1946 [10]. In the following years, many of the crypto-related patents would be registered in his name.
Telekrypto-Gerät 35, a joint development of Gretener and Hagelin.

The co-operation with Hagelin was not restricted to the Telekrypto 35, but dates back to 1947, shortly after Gretag had introduced the ETK-47 teleprinter. Hagelin was particularly interested in these teleprinters, as they were suitable for his foreign customers. As the ETK uses a proprietary 14-bit technology to build a character from the (14) individual segments, it can be modified easily for foreign languages, such as Russian (Cyrillic), without replacing the print head [12].

1958: Gretag AG
After Dr. Edgar Gretener's untimely death on 22 October 1958, the company was taken over by the Swiss chemical company CIBA Holding AG (now: Novartis) who changed the name to Gretag AG. Dr. Robert Käppeli, one of Gretener's finiancial backups, became the new director [7].

Shortly afterwards, the company moved to Regensdorf (near Zürich), where CIBA had secured a large new premises on an industrial estate that provided room for expansion. In the following years new buildings were added and eventually the company would employ over 2500 people. Even today (many years after the demise of Gretag) the area is known as the Gretag-Areal [14].

1962: Business groups
By 1962, the company was producing over 100 different products in a wide variety of fields, including cipher machines, but also devices for the (colour) printing industry. As this was confusing, not only for the employees but also for the customers, CIBA decided to divide the many products into product categories, each of which was supported by a business group [15]:

  1. Arc lamps
  2. Eidophor
  3. Teleprinters, Cipher Machines, electronic devices
  4. Projection screens
  5. Digital technology
  6. Various
  7. Copiers
At this time, Dr. ter Meer is the director of Gretag AG. As part of the takeover by CIBA, all former Gretag patents have been moved over to CIBA, who also manages and monitors them. Some of the early patents were dropped and some other patents were eventually given back to Gretag AG.

1971: Patent Wars
By the late 1960's, Gretag holds a respectable number of world-wide patents, most of which are related to Gretag's ever increasing photographic reproduction business. Nevertheless, the name of Kurt Ehrat, head of the cipher equipment development, appears 6th in the list of people with at least five cryptographic patents in the US, just one place below the famous William Friedman [16].

In the early 1970s, it becomes increasingly difficult to register new patents as more and more 'inventions' are declared 'prior art' in a number of countries. In the photographic business there is a stiff competition with renowned companies like AFGA, KODAK, Fox-Stanley and CA Pieronex. The result is a series of claims from these companies and counter-claims from Gretag.

In the US, it appears to be very difficult to register patents related to high-end electronic cipher equipment, such as the TC-803 and TC-812, in the light of the Secrecy Act of the Department of Defense. This required the patents to be secret and blocked the sales of such machines to the general public. For that reason the patents were not filed in the US, but only in Canada and Japan.

Nevertheless, Gretag kept filing new patents in a variety of fields and by 1976, they had well over 100 patents in their card index. Head of cryptographic developments Kurt Ehrat was arguably the most active cryptographic expert in the company with 23 crypto-related patents in his name, whilst Robert Wahli was the number one with 39 patents, mainly related to the photo-business.

1987: Omnisec
In the late 1980s, it became clear that Gretag's product range was too diverse. Although the crypto-related business was significant and many new systems had been introduced over the years, it was overshadowed by the photographic business. The crypto-business was often related to the army, secrecy and espionage and the owner, CIBA AG, felt increasingly uncomfortable with that. After all, they were a chemical company and were mainly interested in the photographic reproduction systems when they bought Gretag after Dr. Edgar Gretener's death in 1958.

In June 1986, CIBA instructs the Gretag board of directors to find a buyer for the business group 'Authorities' which handles the sales of strategic equipment to foreign governments and armies. In June 1987, the board announces that the business unit will be transferred to the newly established OMNISEC AG, also in Regensdorf.

OMNISEC had been founded especially for this purpose and is fully owned by the all-Swiss ARGONIUM SA, a high-tech holding consortium in Geneva. The new company will be led by Dr. Pierre Schmid, a former employee of Gretag AG.
The current building of OMNISEC at Rietstrasse 14 in Dällikon.

Schmid had left Gretag in 1978 to start working for STR, after leading the development of cipher machines for several years. At least 7 crypto-related patents were registered in his name during his time at Gretag [18]. Approximately 10 Gretag employees were given the option of making the switch to OMNISEC as well, mainly people from the Intelligence Technology section. In July 1987, Gretag's customers were briefed and OMNISEC officially started trading on 1 October 1987.

With the transfer, OMNISEC acquired the production rights of all Gretag cipher machines, with the exception of the civil cipher machines GC-517, 818, 519 and 715, and the machines for the Swiss authorities (GRD). OMNISEC was allowed however, to offer the civil machines abroad as OEM products. Initially the OMNISEC machines were still manufactured at Gretag, but over the years, production was gradually moved over to OMNISEC's own facilities.

1991: AT&T - Gretag Data Systems
Being left with just the civil crypto-market, such as banks and the Swiss Government, the cipher machine devision of Gretag AG became less and less significant. As a result, CIBA finally decided to split-off the cipher-business altogether and, in 1991, sell it to the large American Telecom provider AT&T. The former business unit became a new legal entity: Gretag Data Systems AG.

AT&T Gretacoder 524, a small digital link encryptor. Click for more information.

Many of the systems developed in the following years, such as the Gretacoder 524, would carry the brand name Gretacoder, or AT&T, or both. With the acquisition, AT&T had hoped to get a foot in the Swiss market and get access to systems for safe bank transactions at the same time. It didn't work out well however, as there was strong competition from companies like Crypto AG (Hagelin) and former Gretag-split-off Omnisec AG. In comparison to AT&T's business in the US, the Swiss operation appeared to be minute and AT&T gradually lost interest.

1995: IRE - Gretacoder Data Systems
In October 1995, the company was acquired by Information Resource Engineering Inc. (IRE), a US company that was established in 1987 by two former NSA Engineers. Gretag Data Systems, which had a turnover of $7 million in 1994, was bought for approx. $4 million [4] and the name was subsequently changed to Gretacoder Data Systems AG. Many new cipher machines were produced during this period and all products would carry the brand name Gretacoder.

2002: SafeNet Data Systems
In 1999, the current owner of the company, IRE, was renamed to Safenet, after its VPN product line. A few years later, in 2002, Gretacoder Data Systems was renamed to Safenet Data Systems [6]. Due to domestic and international competition, the Gretacoder business was rapidly declining and Safenet injected signficanly new capital in an attempt to turn the tide.

2004: Demise
Despite the new capital injections, the company did not survive. Finally, late 2004, the board of directors saw itself forced to announce immediate liquidation of the company. Most of the existing business has since been taken over by OMNISEC, who already owned the production rights and most of the patents, and had since moved to Dällikon, just outside of Regensdorf.

The former Gretag buildings at Althartstraße in Regensdorf are still standing today and still carry the name of the once so large company. The estate is now called Gretag-Areal and the buildings are rented in small units to a wide range of different companies [14]. Gretag-Areal is headed by Felix Ruhier, who was once a Group Controller at Gretag (1991-1993) [19].

Known addresses
Gretag, or Gretacoder Data Systems AG, is no longer in business but some of their activities have been taken over by OMNISEC, a company established in 1987 by a former Gretag employee. Support for old Gretag equipment is non-existent however. The last known addresses are:

  1. Ulrich Rimensberger, Datensicherung durch Chiffrierung
    Description of the Gretacoder 515, published at the 5th International Congress for Data Processing in Europe. Vienna, 21-25 March 1977.

  2. Gretacoder Data Systems AG. Gretacoder 650, High-Speed Link Encryptor.
    2-page sales brochure. August 2000.

  3. Gretacoder Data Systems AG. Gretacoder 545, X.25 Data Encryption.
    4-page sales brochure. April 1997.

  4. The Free Library, IRE Acquired Gretag Data Systems AG
    11 June 1995, Retrieved march 2012.

  5. Dr. John H. Nugent, Curriculum Vitae
    Member of Board of Directors at AT&T Gretag 1991-1993.
    31 March 2007. p. 6. Retrieved march 2012.

  6. Business Wire, SafeNet to Expand and Strengthen European Operations...
    Business Library website. Retrieved July 2012.

  7. Wikipedia Germany, Edgar Gretener
    Retrieved May 2013.

  8. Dr Edgar Gretener AG, Telekrypto-Gerät GR tg 35
    Gretag Archives, 1949-1951. Crypto Museum #CM301792.

  9. Gretener AG, Besprechnungsnotiz vom 30. März 1951
    Minutes of meeting concerning delivery of 35 TKG machines to Danmark (German).
    Gretag archives, 3 April 1951. Crypto Museum #CM301792/A.

  10. Gretag AG, Personalmutation Kurt Ehrat
    Interial memo about Kurt Ehrat reaching retirement age (German).
    Gretag Archives, 31 January 1979. Crypto Museum #CM301766.

  11. Schweizerische Bauzeitung, Edgar Gretener. 3 March 1957 - 22 October 1958.
    Obituary (German). 76th edition, Volume 51. 20 December 1958.

  12. Letter from [Oskar] Sturzinger (Hagelin) requesting Cyrillic characters for the ETK-47
    21 March 1947. Retrieved from [13].

  13. Walter Schmid, Der Krypto-Funk-Fernschreiber KFF-58
    October 2008.

  14. Gretag Areal, Regensdorf, Zurich
    Website of the current land owner of the former Gretag buildings.
    Retrieved July 2013.

  15. CIBA AG, Aufteilung der Gretag-Cases in die verschiedenen Sachgebiete
    Creation of Gretag operational divisions (German). Gretag Archives.
    Basel, 17 December 1962. Crypto Museum #CM301793.

  16. US Patent Office, List of inventors with at least five (cryptographic) patents
    Date unknown, but likely to be 1968.

  17. Gretag AG, "Leitfaden" zur Info-Weitergabe am 29.7.87
    Memorandum about the transfer of cipher equipment to OMNISEC AG (German).
    29 July 1987.

  18. Crypto Museum, Gretag AG Patents
    Complete overview and correspondence regarding Gretag Patents 1943 - 1990.
    Gretag Archives, Crypto Museum #CM301767.

  19. Linked-in, Felix Ruhier
    Retrieved July 2013.
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