A photocopier (also known as a copier or copy machine) is a machine that makes copies of documents and other visual images onto paper or plastic film quickly and cheaply. Most modern photocopiers use a technology called xerography, a dry process that uses electrostatic charges on a light-sensitive photoreceptor to first attract and then transfer toner particles (a powder) onto paper in the form of an image. Heat, pressure or a combination of both is then used to fuse the toner onto the paper. Copiers can also use other technologies such as ink jet, but xerography is standard for office copying. Earlier versions included the Gestetner stencil duplicator, invented by David Gestetner in 1887.

Commercial xerographic office photocopying was introduced by Xerox in 1959,[1][2] and it gradually replaced copies made by Verifax, Photostat, carbon paper, mimeograph machines, and other duplicating machines.

Photocopying is widely used in the business, education, and government sectors. While there have been predictions that photocopiers will eventually become obsolete as information workers increase their use of digital document creation, storage and distribution, and rely less on distributing actual pieces of paper, as of 2015, photocopiers continue to be widely used. In the 1980s, there is a convergence in some high-end machines between the roles of a photocopier, a fax machine, a scanner, and a computer network-connected printer into a multi-function printer. Lower-end machines that can copy and print in color have increasingly dominated the home-office market as their prices fell steadily through 1999. Higher-end color photocopiers capable of handling heavy duty cycles and large-format printing remain a costlier specialty for print and design shops.

Fuji Xerox Document Centre 505 and Taiwan Xerox Walk-In 120D at ROC National Central Library 20101211
A Xerox photocopier in 2010


Chester Carlson, the inventor of photocopying, was originally a patent attorney, as well as a part-time researcher and inventor. His job at the patent office in New York required him to make a large number of copies of important papers. Carlson, who was arthritic, found this to be a painful and tedious process. This motivated him to conduct experiments with photo conductivity. Carlson used his kitchen for his "electrophotography" experiments, and, in 1938, he applied for a patent for the process. He made the first photocopy using a zinc plate covered with sulfur. The words "10-22-38 Astoria" were written on a microscope slide, which was placed on top of more sulfur and under a bright light. After the slide was removed, a mirror image of the words remained. Carlson tried to sell his invention to some companies, but failed because the process was still underdeveloped. At the time, multiple copies were most commonly made at the point of document origination, using carbon paper or manual duplicating machines, and people did not see the need for an electronic machine. Between 1939 and 1944, Carlson was turned down by over 20 companies, including IBM and General Electric—neither of which believed there was a significant market for copiers.

In 1944, the Battelle Memorial Institute, a non-profit organization in Columbus, Ohio, contracted with Carlson to refine his new process. Over the next five years, the institute conducted experiments to improve the process of electrophotography. In 1947, Haloid Corporation (a small New York-based manufacturer and seller of photographic paper) approached Battelle to obtain a license to develop and market a copying machine based on this technology.[2]

Haloid felt that the word "electrophotography" was too complicated and did not have good recall value. After consulting a professor of classical language at Ohio State University, Haloid and Carlson changed the name of the process to "xerography", which was derived from Greek words that meant "dry writing". Haloid called the new copier machines "Xerox Machines" and, in 1948, the word "Xerox" was trademarked. Haloid eventually changed its name to Xerox Corporation.

In 1949, Xerox Corporation introduced the first xerographic copier called the Model A.[3] Defeating computer leader IBM,[4] Xerox became so successful that, in North America, photocopying came to be popularly known as "xeroxing". Xerox has actively fought to prevent "Xerox" from becoming a genericized trademark. While the word "Xerox" has appeared in some dictionaries as a synonym for photocopying, Xerox Corporation typically requests that such entries be modified, and that people not use the term "Xerox" in this way. Some languages include hybrid terms, such as the widely used Polish term kserokopia ("xerocopy"), even though relatively few photocopiers are of the Xerox brand.

In the early 1950s, Radio Corporation of America (RCA) introduced a variation on the process called Electrofax, whereby images are formed directly on specially coated paper and rendered with a toner dispersed in a liquid.

During the 1960s and through the 1980s, Savin Corporation developed and sold a line of liquid-toner copiers that implemented a technology based on patents held by the company.

Before the widespread adoption of xerographic copiers, photo-direct copies produced by machines such as Kodak's Verifax were used. A primary obstacle associated with the pre-xerographic copying technologies was the high cost of supplies: a Verifax print required supplies costing US$0.15 in 1969, while a Xerox print could be made for $0.03 including paper and labor. The coin-operated Photostat machines still found in some public libraries in the late 1960s made letter-size copies for $0.25 each, at a time when the minimum wage for a US worker was $1.65 per hour; the Xerox machines that replaced them typically charged $0.10.

Xerographic copier manufacturers took advantage of a high perceived-value of the 1960s and early 1970s, and marketed paper that was "specially designed" for xerographic output. By the end of the 1970s, paper producers made xerographic "runability" one of the requirements for most of their office paper brands.

DADF (Canon IR6000)
DADF or Duplex Automatic Document feeder - Canon IR6000

Some devices sold as photocopiers have replaced the drum-based process with inkjet or transfer film technology.

Among the key advantages of photocopiers over earlier copying technologies are their ability:

  • to use plain (untreated) office paper;
  • to implement duplex (or two-sided) printing;
  • to scan several pages automatically with an ADF; and,
  • eventually, to sort and/or staple output.

Color photocopiers

Colored toner became available in the 1950s, although full-color copiers were not commercially available until 3M released the Color-in-Color copier in 1968, which used a dye sublimation process rather than conventional electrostatic technology. The first electrostatic color copier was released by Xerox (the 6500) in 1973. Color photocopying is a concern to governments, as it facilitates counterfeiting currency and other documents: for more information, see Counterfeiting section.

Digital technology

There is an increasing trend for new photocopiers to adopt digital technology, thus replacing the older analog technology. With digital copying, the copier effectively consists of an integrated scanner and laser printer. This design has several advantages, such as automatic image quality enhancement and the ability to "build jobs" (that is, to scan page images independently of the process of printing them). Some digital copiers can function as high-speed scanners; such models typically offer the ability to send documents via email or to make them available on file servers.

A great advantage of digital copier technology is "automatic digital collation". For example, when copying a set of 20 pages 20 times, a digital copier scans each page only once, then uses the stored information to produce 20 sets. In an analog copier, either each page is scanned 20 times (a total of 400 scans), making one set at a time, or 20 separate output trays are used for the 20 sets.

Low-end copiers also use digital technology, but tend to consist of a standard PC scanner coupled to an inkjet or low-end laser printer, both of which are far slower than their counterparts in high-end copiers. However, low-end scanner-inkjets can provide color copying at a lower purchase price but with a much higher cost per copy. The cost of electronics is such that combined scanner-printers sometimes have built-in fax machines. (See Multifunction printer.)

How it works (using xerography)

Xerographic photocopy process en
Schematic overview of the xerographic photocopying process (step 1-4)
  1. Charging: cylindrical drum is electrostatically charged by a high voltage wire called a corona wire or a charge roller. The drum has a coating of a photoconductive material. A photoconductor is a semiconductor that becomes conductive when exposed to light.[5]
  2. Exposure: A bright lamp illuminates the original document, and the white areas of the original document reflect the light onto the surface of the photoconductive drum. The areas of the drum that are exposed to light become conductive and therefore discharge to the ground. The area of the drum not exposed to light (those areas that correspond to black portions of the original document) remains negatively charged.
  3. Developing: The toner is positively charged. When it is applied to the drum to develop the image, it is attracted and sticks to the areas that are negatively charged (black areas), just as paper sticks to a balloon with a static charge.
  4. Transfer: The resulting toner image on the surface of the drum is transferred from the drum onto a piece of paper that has an even greater negative charge than the drum has.
  5. Fusing: The toner is melted and bonded to the paper by heat and pressure rollers.

A negative photocopy inverts the colors of the document when creating a photocopy, resulting in letters that appear white on a black background instead of black on a white background. Negative photocopies of old or faded documents sometimes produce documents which have better focus and are easier to read and study.

Copyright issues

Photocopying material that is subject to copyright (such as books or scientific papers) is subject to restrictions in most countries. This is common practice, as the cost of purchasing a book for the sake of one article or a few pages can be excessive. The principle of fair use (in the United States) or fair dealing (in other Berne Convention countries) allows copying for certain specified purposes.

In certain countries, such as Canada, some universities pay royalties from each photocopy made at university copy machines and copy centers to copyright collectives out of the revenues from the photocopying, and these collectives distribute resulting funds to various scholarly publishers. In the United States, photocopied compilations of articles, handouts, graphics, and other information called readers are often required texts for college classes. Either the instructor or the copy center is responsible for clearing copyright for every article in the reader, and attribution information must be clearly included in the reader.


To counter the risk of people using color copiers to create counterfeit copies of paper currency, some countries have incorporated anti-counterfeiting technologies into their currency. These include watermarks, microprinting, holograms, tiny security strips made of plastic (or other material), and ink that appears to change color as the currency is viewed at an angle. Some photocopying machines contain special software that can prevent copying currency that contains a special pattern.

Color copying also raises concerns regarding the copying and/or forging of other documents as well, such as driver's licenses and university degrees and transcripts. Some driver's licenses are made with embedded holograms so that a police officer can detect a fake copy. Some university and college transcripts have special anti-copying watermarks in the background. If a copy is made, the watermarks will become highly visible, which allows the recipient to determine that they have a copy rather than a genuine original transcript.

Health issues

Exposure to ultraviolet light is a concern. In the early days of photocopiers, the sensitizing light source was filtered green to match the optimal sensitivity of the photoconductive surface. This filtering conveniently removed all ultraviolet.[6] Currently, a variety of light sources are used. As glass transmits ultraviolet rays between 325 and 400 nanometers, copiers with ultraviolet-producing lights such as fluorescent, tungsten halogen, or xenon flash, expose documents to some ultraviolet.[6]

Concerns about emissions from photocopy machines have been expressed by some in connection with the use of selenium and emissions of ozone and fumes from heated toner.[7][8]

Forensic identification

Similar to forensic identification of typewriters, computer printers and copiers can be traced by imperfections in their output. The mechanical tolerances of the toner and paper feed mechanisms cause banding, which can reveal information about the individual device's mechanical properties. It is often possible to identify the manufacturer and brand, and, in some cases, the individual printer can be identified from a set of known printers by comparing their outputs.[9]

Some high-quality color printers and copiers steganographically embed their identification code into the printed pages, as fine and almost invisible patterns of yellow dots. Some sources identify Xerox and Canon as companies doing this.[10][11] The Electronic Frontier Foundation (EFF) has investigated this issue[12] and documented how the Xerox DocuColor printer's serial number, as well as the date and time of the printout, are encoded in a repeating 8×15 dot pattern in the yellow channel. EFF is working to reverse engineer additional printers.[13] The EFF also reports that the US government has asked these companies to implement such a tracking scheme, so that counterfeiting can be traced. The EFF has filed a Freedom of Information Act request in order to look into privacy implications of this tracking.[14]

See also


  1. ^ "Xerox History: 1950s". Retrieved 28 September 2017.
  2. ^ a b "The Story of Xerography" (PDF). Xerox Corporation. Retrieved 28 September 2017.
  3. ^ "Xerox history: 1940s". Retrieved 28 September 2017.
  4. ^ Greenwald, John (1983-07-11). "The Colossus That Works". TIME. Archived from the original on 2008-05-14. Retrieved 2019-05-18. Cite uses deprecated parameter |dead-url= (help)
  5. ^ "Encarta definition of 'photoconductor'". Archived from the original on 2008-12-11. Retrieved 2009-11-20. Cite uses deprecated parameter |deadurl= (help)
  6. ^ a b "Photocopier Hazards and a Conservation Case Study (notes 17,18)". Retrieved 2009-11-20.
  7. ^ "Photocopier and Laser Printer Hazards" (PDF). London Hazards Centre. 2002. Archived from the original (PDF) on 2010-04-01. Retrieved 2009-11-20. Cite uses deprecated parameter |deadurl= (help)
  8. ^ "Health and Safety Representatives' Handbook". [National Association of Schoolmasters Union of Women Teachers (NASUWT)]. July 27, 2009. Archived from the original (PDF) on July 19, 2011. Retrieved April 30, 2011. Cite uses deprecated parameter |deadurl= (help)
  9. ^ "Printer forensics to aid homeland security, tracing counterfeiters". 2004-10-12. Retrieved 2009-11-20.
  10. ^ Jason Tuohey (2004-11-22). "Government Uses Color Laser Printer Technology to Track Documents". Retrieved 2009-11-20.
  11. ^ Wilbert de Vries (2004-10-26). "Dutch track counterfeits via printer serial numbers". Retrieved 2009-11-20.
  12. ^ "Is Your Printer Spying On You?". Electronic Frontier Foundation. Retrieved 2009-11-20.
  13. ^ "List of Printers Which Do or Do Not Display Tracking Dots". Electronic Frontier Foundation. Retrieved 2009-11-20.
  14. ^ "Printers". Electronic Frontier Foundation.

Further reading

  • R. Schaffert: Electrophotography. Focal Press, 1975
  • Owen, David (August 2004). Copies in Seconds : How a Lone Inventor and an Unknown Company Created the Biggest Communication Breakthrough Since Gutenberg: Chester Carlson and the Birth of the Xerox Machine. New York: Simon & Schuster. ISBN 0-7432-5117-2.
Copier (disambiguation)

A copier or photocopier is a machine for producing paper duplicates of documents and images.

Copier may also refer to:

Mettin Copier, a footballer currently playing for Dayton Dutch Lions

Game backup device

Slide copier, a device for duplicating photographic slides

Correction fluid

A correction fluid or white-out is an opaque, usually white, fluid applied to paper to mask errors in text. Once dried, it can be written over. It is typically packaged in small bottles, and the lid has an attached brush (or a triangular piece of foam) which dips into the bottle. The brush is used to apply the fluid onto the paper. It can be used for many purposes.

Before the invention of word processors, correction fluid greatly facilitated the production of typewritten documents.

One of the first forms of correction fluid was invented in 1956 by the secretary Bette Nesmith Graham, founder of Liquid Paper.With the advent of coloured paper stocks for office/typing/photocopier use, correction fluid manufacturers began producing their product in various colours, particularly reds, blues, and yellows, so that corrections made on these papers would be less visually invasive.

Georgi Nadjakov

Georgi Nadjakov (also spelled Georgi Nadzhakov) (Bulgarian: Георги Наджаков) (26 December 1896 – 24 February 1981) was a Bulgarian physicist. He became a corresponding member of the Göttingen Academy of Sciences (1940) in Germany, member of the Bulgarian Academy of Sciences (1945) and member of the Russian Academy of Sciences (1958).

Sofia University sent him to specialize in the laboratories of Paul Langevin and Marie Curie in Paris, where he investigated photoelectricity for one year.

Georgi Nadjakov experimentally investigated photoconducting properties of sulphur. He prepared the permanent photoelectret state of matter for the first time and published his paper in 1937

and 1938. He called the electret discovered by Mototaro Eguchi in 1919, thermoelectret and the electret discovered by him in 1937, photoelectret.

Photoelectrets were the most notable achievement of Georgi Nadjakov. Its practical application led to the invention of the photocopier by Chester Carlson some years later.

International Society of Copier Artists

The International Society of Copier Artists (I.S.C.A) was a non-profit group founded by Louise Neaderland in 1981, intended to promote the work of photocopier artists who used the copier as a camera with which to scan and print original and experimental signed limited-edition compositions. I.S.C.A advocated for the recognition of copier art as a legitimate art form. The group is best known for producing The I.S.C.A Quarterly as well as for coordinating exhibitions of xerographic artwork, and the distribution of "The I.S.C.A Newsletter". Women made up the majority of the society's membership.

Jobbing press

A jobbing press, job press, or jobber is a variety of printing press used in letterpress printing.The press is meant to be operated by a pressman working on small jobs, as opposed to long print runs or newspaper work, or jobs that require less than a full-sized sheet of paper, though the definition of "small jobs" may vary widely depending on the printing shop. Such work might include printing personal stationery, handbills, or other small printing jobs, or may include even a small book. Such presses were common in the later 19th and 20th centuries, have yet been largely replaced by the photocopier for small and medium runs, and by the desktop computer for personal stationery. Today, the jobber is the preferred press for letterpress printers who now produce high-end prints (often wedding invitations) for customers who want an antique effect.

Though the term can refer to any small printing press or machine intended for such work, it most commonly refers to a class of small, vertical platen presses.

Depending on the time-period when the machine was made, they may be operated by treadle, line shaft, electricity, or by hand lever.

Katana (photocopier)

Katana is the name given to a Ricoh photocopier. It is a high volume machine that is able to copy at speeds of up to 135 pages per minute, while the slowest Katana copier can copy at 90 copies per minute. It is a black and white machine but has a color scanner fitted to it. It can be used as both a photocopier and printer at the same time.

Kill the Man

Kill the Man is a 1999 American comedy film starring Luke Wilson and Joshua Malina as the owners of an independent photocopier shop who are in competition with a large chain of copy-shops.


Liskom, Ltd. is a vending machine manufacturing company based in Moscow, Russia. The mainstream product of the company is coin- and bill-operated photocopier "Kopirkin".

Liskom was the first company in Russia to manufacture the vending photocopier what is confirmed by utility model patent (RU70010 (U1)) hold by company.

At the moment Liskom is one of the largest and well-known companies on Russian vending machines manufacturing market.

Multi-function printer

An MFP (multi-function product/printer/peripheral), multi-functional, all-in-one (AIO), or multi-function device (MFD), is an office machine which incorporates the functionality of multiple devices in one, so as to have a smaller footprint in a home or small business setting (the SOHO market segment), or to provide centralized document management/distribution/production in a large-office setting. A typical MFP may act as a combination of some or all of the following devices: email, fax, photocopier, printer, scanner.

Operating expense

An operating expense, operating expenditure, operational expense, operational expenditure or opex is an ongoing cost for running a product, business, or system. Its counterpart, a capital expenditure (capex), is the cost of developing or providing non-consumable parts for the product or system. For example, the purchase of a photocopier involves capex, and the annual paper, toner, power and maintenance costs represents opex. For larger systems like businesses, opex may also include the cost of workers and facility expenses such as rent and utilities.

Pati Hill

Pati Hill (April 3, 1921 - September 19, 2014) was an American writer and photocopy artist best known for her observational style of prose and her work with the IBM photocopier. While she was not the first artist to experiment with the copier, her work is distinguished by its focus on objects, her emphasis on the accessibility of the medium, and her efforts to unite image and text so that they may "fuse to become something other than either."

Photostat machine

The Photostat machine, or Photostat, was an early projection photocopier created in the decade of the 1900s by the Commercial Camera Company, which became the Photostat Corporation. The "Photostat" name, which was originally a trademark of the company, became genericized, and was often used to refer to similar machines produced by the Rectigraph Company.

Push broom scanner

A push broom scanner, also known as an along-track scanner, is a device for obtaining images with spectroscopic sensors. The scanners are regularly used for passive remote sensing from space, and in spectral analysis on production lines, for example with near-infrared spectroscopy used to identify contaminated food and feed. The moving scanner line in a traditional photocopier (or a scanner or facsimile machine) is also a familiar, everyday example of a push broom scanner. Push broom scanners and the whisk broom scanners variant (also known as across-track scanners) are often contrasted with staring arrays (such as in a digital camera), which image objects without scanning, and are more familiar to most people.

In orbital push broom sensors, a line of sensors arranged perpendicular to the flight direction of the spacecraft is used. Different areas of the surface are imaged as the spacecraft flies forward. A push broom scanner can gather more light than a whisk broom scanner because it looks at a particular area for a longer time, like a long exposure on a camera. One drawback of pushbroom sensors is the varying sensitivity of the individual detectors. These sensors are also known as survey or wide field devices, comparable to wide angle lenses on conventional cameras.Examples of spacecraft cameras using push broom imagers include Mars Express's High Resolution Stereo Camera, Lunar Reconnaissance Orbiter Camera NAC, Mars Global Surveyor's Mars Orbiter Camera WAC, and the Multi-angle Imaging SpectroRadiometer on board the Terra satellite.


Risograph is a brand of digital duplicators manufactured by the Riso Kagaku Corporation, that are designed mainly for high-volume photocopying and printing. It was released in Japan in August 1986. It is sometimes called a digital duplicator or printer-duplicator, as newer models can be used as a network printer as well as a stand-alone duplicator. When printing or copying many duplicates (generally more than 20) of the same content, it is typically far less expensive per page than a conventional photocopier, laser printer, or inkjet printer.

Savin (photocopiers)

Savin was incorporated in 1959 by Max M. and Robert K.Low (the company was named using the name of Max Low's son-in-law, Robert S. Savin) and was run by Low's son, Robert K. Low (Finance, management and marketing) and E. Paul Charlap (research and development). It was known primarily for its line of liquid toner photocopiers, which set it apart from other companies that manufactured dry toner equipment, like Xerox.

During the 1960s and through the 1980s, Savin developed and sold a line of liquid-toner copiers that implemented a technology based on patents held by the company. Savin's copiers were manufactured by Ricoh Company and distributed by Savin in the US and Canada through 50 Branch offices and 500 dealers, and under licenses from Savin to Nashua Corp for Europe and South America and through Ricoh for the Far East. Although up against major corporations such as Xerox, IBM and Kodak, Savin was able to find its niche with well-developed marketing plans. Savin ( approximate sales of $500 million and royalties from licensees of $10 million) was listed on the New York Stock Exchange when it was sold in 1982 to Canadian Development Corp and later sold to other companies. The acquiring companies never had the marketing talent (deciding not to keep the talented Savin marketing professionals that had built the Company) and, therefore, sales and royalties began to decline at a steady pace.

Savin also works in other than the USA and their website for Asia and Europe Specific is


Savin dealers in USA (SAVIN Dealers in USA)

Savin dealers in other countries(Dealers Location)

In 1995, Ricoh Company acquired Savin Corporation, at which time it was made a wholly owned sales subsidiary.

Secretarial pool

A secretarial pool or typing pool is a group of secretaries working at a company available to assist any executive without a permanently assigned secretary. These groups have been reduced or eliminated where executives have been assigned responsibility for writing their own letters and other secretarial work.

After the widespread adoption of the typewriter but before the photocopier and personal computer, pools of typists were needed by large companies to produce documents from handwritten manuscripts, re-type documents that had been edited, type documents from audio recordings, or to type copies of documents.

The Surplus

"The Surplus" is the tenth episode of the fifth season of the television series The Office, and the show's eighty-second episode overall. The episode aired in the United States on December 4, 2008 on NBC.

In this episode, the office is at odds over whether to spend a budget surplus on new chairs or a new photocopier, with Jim, Pam, and Oscar in particular trying to convince Michael how to spend the money. Meanwhile, Andy and Angela visit Schrute Farms to discuss their wedding plans.

Two Weeks (The Office)

"Two Weeks" is the twenty-first episode of the fifth season of the television series The Office, and the 93rd overall episode of the series. It originally aired on NBC in the United States on March 26, 2009. In this episode, Michael, who has given his two weeks' notice to Dunder Mifflin, tries to convince others in the office to quit and join him in starting a new paper company. Meanwhile, Pam spends her day trying to put together the new photocopier and becomes frustrated with her job.

The episode was written by Aaron Shure and directed by Paul Lieberstein. Executive story editor Charlie Grundy conceived the idea of Michael leaving Dunder Mifflin, and the writers collectively decided the Pam character should leave and try to find out what she wants from life. The episode included a guest appearance by Idris Elba, who played new Dunder Mifflin vice president Charles Miner. "Two Weeks" received generally positive reviews and, according to Nielsen ratings, was watched by 8.7 million overall viewers and was the top-rated show on NBC the week it aired. "Two Weeks" received a Primetime Emmy Award nomination for Outstanding Single-Camera Picture Editing for a Comedy Series.


Xerography or electrophotography is a dry photocopying technique. Its fundamental principle was invented by American physicist Chester Carlson and based on Hungarian physicist Pál Selényi's publications. Chester Carlson applied for and was awarded U.S. Patent 2,297,691 on October 6, 1942. The technique was originally called electrophotography. It was later renamed xerography—from the Greek roots ξηρός xeros, "dry" and -γραφία -graphia, "writing"—to emphasize that, unlike reproduction techniques then in use such as cyanotype, this process used no liquid chemicals.Carlson's innovation combined electrostatic printing with photography, unlike the dry electrostatic printing process invented by Georg Christoph Lichtenberg in 1778. Carlson's original process was cumbersome, requiring several manual processing steps with flat plates. It was almost 18 years before a fully automated process was developed, the key breakthrough being use of a cylindrical drum coated with selenium instead of a flat plate. This resulted in the first commercial automatic copier, the Xerox 914, being released by Haloid/Xerox in 1960. Before that year, Carlson had proposed his idea to more than a dozen companies, but none were interested. Xerography is now used in most photocopying machines and in laser and LED printers.


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