Editing Duopoly (section)

==Examples in business==
<!-- Do not add examples without providing a reliable source that characterizes them as duopolies. The source need not use the word "duopoly," but it must note the anticompetitive effect of a two-entity market. Your own opinion is not sufficient. -->
A commonly cited example of a duopoly is that involving [[Visa Inc.|Visa]] and [[Mastercard]], who between them control a large proportion of the electronic payment processing market. In 2000 they were the defendants in a [[United States Department of Justice]] [[Sherman Antitrust Act|antitrust]] lawsuit.<ref>{{cite web|url=https://www.justice.gov/atr/case-document/file/992401/download|title=Complaint for Equitable Relief for Violations of 15 U.S.C. § 1: U.S. v. Visa U.S.A., et al.|format=PDF|publisher=[[United States Department of Justice|U.S. Department of Justice]]|website=justice.gov|date=October 7, 1998|access-date=January 18, 2023}}</ref><ref>{{cite journal|url=http://mit.edu/thistle/www/v12/2/credit.html|date=July 4, 2000|archive-url=https://web.archive.org/web/20020902064409/http://mit.edu/thistle/www/v12/2/credit.html|archive-date=September 2, 2002|title=Credit Card Antitrust Suit|journal=The Thistle|volume=12|number=2|access-date=January 18, 2023}}</ref> An appeal was upheld in 2004.<ref>{{cite news|url=http://news.bbc.co.uk/1/hi/business/4014599.stm|title=Amex is suing Visa and Mastercard|date=November 15, 2004|access-date=January 18, 2023|work=[[BBC News]]}}</ref>

Examples where two companies control an overwhelming proportion of a market are:

* [[Airbus]] and [[Boeing]] in the largest commercial aircraft market in the world
* [[Nvidia]] (who acquired competitor [[3dfx]] in 2002) and [[AMD]] (formerly [[ATI Technologies|ATI]] which AMD acquired in 2006) in the [[GPU]] market
* [[Intel]] and [[AMD]] in the desktop [[Central processing unit|CPU]] market
* [[Google]]'s [[Android (operating system)|Android]] and [[Apple Inc|Apple's]] [[iOS]] make up over 99% of the [[mobile operating system]] market<ref>{{cite news|url=https://www.theverge.com/2017/2/16/14634656/android-ios-market-share-blackberry-2016|title=99.6 percent of new smartphones run Android or iOS|last=Vincent|first=James|work=[[The Verge]]|date=February 16, 2017|access-date=January 18, 2023}}</ref><ref>{{Cite web|title=Mobile Operating System Market Share Worldwide|url=https://gs.statcounter.com/os-market-share/mobile/worldwide|access-date=January 18, 2023|publisher=[[StatCounter]]|website=gs.statcounter.com}}</ref>
* [[The Coca-Cola Company|Coca-Cola]] and [[PepsiCo|Pepsi]] in the [[soft drink]] market, resulting in the [[cola wars]]. The two companies control nearly all of the cola beverage market.
* [[DC Comics|DC]] and [[Marvel Comics|Marvel]] in the [[American comic book]] market and movies<ref>{{cite web|last=Miller|first=John Jackson|author-link=John Jackson Miller|title=2017 Comic Book Sales to Comics Shops|url=http://www.comichron.com/monthlycomicssales/2017.html|website=Comichron|access-date=January 23, 2018|quote=Share of Overall Units—Marvel 38.30%, DC 33.93%; Share of Overall Dollars—Marvel 36.36%, DC 30.07%|archive-url=https://web.archive.org/web/20180123131602/http://www.comichron.com/monthlycomicssales/2017.html|archive-date=January 23, 2018|url-status=live}}</ref><ref name=ic>{{cite news|title=Big Two Comic Publishers Lose Share|url=http://icv2.com/articles/comics/view/27580/big-two-comic-publishers-lose-share|access-date=September 22, 2015|work=[[ICv2]]|date=January 8, 2014|archive-url=https://web.archive.org/web/20160205190619/http://icv2.com/articles/comics/view/27580/big-two-comic-publishers-lose-share|archive-date=February 5, 2016|url-status=live}}</ref>
* [[Woolworths Supermarkets|Woolworths]] and [[Coles Supermarkets|Coles]] in the [[Australia]]n supermarket market
* [[Walmart]] and [[Target Corporation|Target]] in the [[America]]n supermarket market
* [[Myer]] and [[David Jones (department store)|David Jones]] in the [[Australia]]n upmarket department store market
* [[Ford Australia]] and [[Holden]] in the [[Australian automotive industry]]<ref>{{Cite news |last=Nicastri |first=Timothy |date=2017-10-04 |title=Ford v Holden: What's behind this uniquely Australian rivalry? |url=https://www.abc.net.au/news/2017-10-05/ford-vs-holden-whats-behind-this-uniquely-australian-rivalry/9013842 |url-status=live |archive-url=https://web.archive.org/web/20180929115056/http://www.abc.net.au/news/2017-10-05/ford-vs-holden-whats-behind-this-uniquely-australian-rivalry/9013842 |archive-date=2018-09-29 |access-date=2025-04-12 |work=[[ABC News (Australia)|ABC News]]}}</ref>
* [[Husqvarna Group|Husqvarna]] and [[Stihl]] in the [[chainsaw]] market
* [[WWE|World Wrestling Entertainment (then World Wrestling Federation)]] and [[World Championship Wrestling]] in the [[professional wrestling|professional wrestling industry]] of the 1980s and 90s, resulting in the [[Monday Night Wars]]
* [[Microsoft Windows|Windows]] and [[macOS]] in the desktop [[operating system]] (OS) market.
* [[Kesko]] and [[S Group]] together hold a 85% market share of grocery stores in [[Finland]].<ref>{{Cite web |date=2017 |title=Päivittäistavarakaupan Duopoli-asetelma Suomessa |trans-title=Duopoly in Finnish Grocery Trade |url=https://www.theseus.fi/bitstream/handle/10024/138392/Toivanen_Kai.pdf;jsessionid=761F09EB2D959564DADA7E2F99DC5570?sequence=2}}</ref><ref>{{Cite web |title=S-Group & Kesko with bigger combined share online than offline |url=https://adainsights.com/blog/s-group-amp-kesko-with-bigger-combined-share-online-than-offline |access-date=2024-12-04 |website=Ada Insights |language=en-US}}</ref>
* [[Christie's]] and [[Sotheby's]] sell more than 80% of works priced over $1m at auction.<ref>{{Cite web |date=2018 |title=Why the Christie's and Sotheby's duopoly is impregnable|url=https://www.theartnewspaper.com/2018/11/22/why-the-christies-and-sothebys-duopoly-is-impregnable}}</ref>