Editing Atari 2600 (section)

===Third-party development===
[[Activision]], formed by Crane, Whitehead, and Miller in 1979, started developing third-party VCS games using their knowledge of VCS design and programming tricks and began releasing games in 1980. ''[[Kaboom! (video game)|Kaboom!]]'' (1981) and ''Pitfall!'' (1982) are among the most successful with at least one and four million copies sold, respectively.<ref name="gi activision start">{{cite magazine | url = https://www.gameinformer.com/b/features/archive/2013/02/26/activisionaries-how-four-programmers-changed-the-game-industry-forever.aspx | title = Activisionaries: How Four Programmers Changed The Game Industry | first = Ben | last = Reeves | date = February 26, 2013 | access-date = April 2, 2021 | magazine = [[Game Informer]] | archive-date = January 27, 2021 | archive-url = https://web.archive.org/web/20210127015005/https://www.gameinformer.com/b/features/archive/2013/02/26/activisionaries-how-four-programmers-changed-the-game-industry-forever.aspx | url-status = live }}</ref> In 1980, Atari attempted to block the sale of the Activision cartridges, accusing the four of intellectual property infringement. The two companies settled out of court, with Activision agreeing to pay Atari a licensing fee for their games. This made Activision the first third-party video game developer and established the licensing model that continues to be used by console manufacturers for game development.<ref name="Gamasutra">{{cite web |url=https://www.gamedeveloper.com/business/the-history-of-activision |title=The History Of Activision |work=Gamasutra |first=Jeffrey |last=Flemming |access-date=December 30, 2016 |url-status=live |archive-url=https://web.archive.org/web/20161220122651/http://www.gamasutra.com/view/feature/1537/the_history_of_activision.php?print=1 |archive-date=December 20, 2016}}</ref>

Activision's success led to the establishment of other third-party VCS game developers following Activision's model in the early 1980s,<ref>{{cite magazine |url=https://books.google.com/books?id=ZD4EAAAAMBAJ&pg=PP1 |title=Atari Sues to k.o. Competition |magazine=InfoWorld |volume=2 |issue=13 |date=August 4, 1980 |page=1 |access-date=March 30, 2014 |archive-date=October 20, 2023 |archive-url=https://web.archive.org/web/20231020183642/https://books.google.com/books?id=ZD4EAAAAMBAJ&pg=PP1#v=onepage&q&f=false |url-status=live }}</ref><ref>{{cite magazine |url=https://books.google.com/books?id=ej0EAAAAMBAJ&pg=PA1 |title=Atari attempts to gobble software competition |author=John Markoff |magazine=InfoWorld |date=December 21, 1981 |page=1 |volume=3 |issue=31 |access-date=March 30, 2014 |archive-date=October 20, 2023 |archive-url=https://web.archive.org/web/20231020183658/https://books.google.com/books?id=ej0EAAAAMBAJ&pg=PA1#v=onepage&q&f=false |url-status=live }}</ref><ref>{{cite book |url=https://books.google.com/books?id=deBFx7QAwsQC&q=atari+activision+1981&pg=PA6 |title=Encyclopedia of Video Games: The Culture, Technology, and Art of Gaming |volume=2 |author=Mark P. Wolf |publisher=ABC-CLIO |year=2012 |isbn=9780313379369 |page=6 |access-date=March 30, 2014 |archive-date=October 20, 2023 |archive-url=https://web.archive.org/web/20231020183636/https://books.google.com/books?id=deBFx7QAwsQC&q=atari+activision+1981&pg=PA6 |url-status=live }}</ref> including [[U.S. Games]], [[Telesys]], [[Games by Apollo]], [[Data Age]], [[Zimag]], [[Mystique (company)|Mystique]], and [[CommaVid]]. The founding of [[Imagic]] included ex-Atari programmers. Mattel and Coleco, each already producing its own more advanced console, created simplified versions of their existing games for the 2600. Mattel used the [[M Network]] brand name for its cartridges. Third-party games accounted for half of VCS game sales by 1982.<ref>{{cite news|last=Rosenberg|first=Ron|title=Competitors Claim Role in Warner Setback|url=https://pqasb.pqarchiver.com/boston/access/666912291.html?FMT=ABS&FMTS=ABS:FT&type=current&date=Dec+11%2C+1982&author=Ron+Rosenberg+Globe+Staff&pub=Boston+Globe+%28pre-1997+Fulltext%29&desc=COMPETITORS+CLAIM+ROLE+IN+WARNER+SETBACK&pqatl=google|access-date=March 6, 2012|newspaper=[[The Boston Globe]]|date=December 11, 1982|page=1|archive-date=November 7, 2012|archive-url=https://web.archive.org/web/20121107073803/http://pqasb.pqarchiver.com/boston/access/666912291.html?FMT=ABS&FMTS=ABS:FT&type=current&date=Dec+11%2C+1982&author=Ron+Rosenberg+Globe+Staff&pub=Boston+Globe+%28pre-1997+Fulltext%29&desc=COMPETITORS+CLAIM+ROLE+IN+WARNER+SETBACK&pqatl=google|url-status=dead}}</ref>