Question: Grand Theft Auto: The Ballad of Gay Tony was an expansion for the game published by which company?

Context articles: List of Grand Theft Auto V characters
Grand Theft Auto: The Lost and Damned
Grand Theft Auto: Vice City Stories
Controversies surrounding Grand Theft Auto IV
Grand Theft Auto: The Ballad of Gay Tony
Development of Grand Theft Auto V
Grand Theft Auto III
Grand Theft Auto IV
Grand Theft Auto (Game Boy Advance)
Grand Theft Auto: Liberty City Stories

Rockstar North's 2013 open world action-adventure video game "Grand Theft Auto V", published by Rockstar Games, deals with a trio of criminals and their efforts to commit heists while under pressure from a corrupt government agency.
 The game's use of three lead protagonists is a break from series tradition.
 Three days after its release, "Grand Theft Auto V" had earned more than US $1 billion in sales, making it the fastest selling video game in history.
 Additionally, "Grand Theft Auto V" was voted Game of the Year from several gaming publications.
 The game's characters were created by writers Dan Houser and Rupert Humphries.
 The use of multiple lead protagonists, as well as the cast in general, has received generally positive reviews from gaming magazines and websites.
Grand Theft Auto IV: The Lost and Damned is the first of two episodic expansion packs developed for the Xbox 360, PlayStation 3 and PC versions of "Grand Theft Auto IV", developed by Rockstar North and published by Rockstar Games.
 It was first released for the Xbox 360 on 17 February 2009 and on PlayStation 3 and Microsoft Windows on 13 April 2010.
 It is the third expansion pack game in the "Grand Theft Auto" series (the first since "", released in 1999), and the twelfth release overall.
Grand Theft Auto: Vice City Stories is an open world action-adventure video game developed by Rockstar Leeds in conjunction with Rockstar North and published by Rockstar Games.
 Released on 31 October 2006 for the PlayStation Portable and later for the PlayStation 2 on 5 March 2007.
 The game is the tenth instalment in the "Grand Theft Auto" series and the sixth and last game in the 3D universe.
 This was also the last game in the series to use well-known and Hollywood voice talent; "Grand Theft Auto IV" onward would instead use lesser-known and unknown voice actors.
 It is a prequel to "" and successor to the previous PSP release, "".
 Vice City is a representation of Miami, Florida.
"Grand Theft Auto IV" is an open world, action-adventure video game developed by Rockstar North and published by Rockstar Games.
 Upon its release on 29 April 2008 for the PlayStation 3 and Xbox 360, "Grand Theft Auto IV" generated controversy.
 The game's depiction of violence received mass commentary from journalists and government officials, occasionally being referred to as a "murder simulator".
 The ability to drive under the influence of alcohol in the game also received criticism, resulting in a request for the ESRB to change the game's rating.
 Similarly, some gameplay features were censored for the Australian and New Zealand versions of the game, though these censors were subsequently removed.
 Several crimes that were committed following the game's release, such as murder and sexual violence, were attributed to the perpetrators' experience with the game, generating further controversy.
 Former attorney Jack Thompson, known for his campaigns against the series, heavily criticised "Grand Theft Auto IV" prior to its release, filing lawsuits against parent company Take-Two Interactive, and threatening to ban distribution of the game if some gameplay features were not removed.
 The game also generated further controversy and lawsuits from city officials and organisations.
Grand Theft Auto: The Ballad of Gay Tony is the second of the two episodic expansion packs available for the PlayStation 3, Microsoft Windows and Xbox 360 versions of "Grand Theft Auto IV", developed by Rockstar North.
 It was first released for the Xbox 360 on 29 October 2009, before then being released for the PlayStation 3 and Microsoft Windows on 13 April 2010.
 It is the fourth expansion pack in the "Grand Theft Auto" series and the 14th release on the series.
An approximately 1,000-person team developed "Grand Theft Auto V", an action-adventure video game, over several years.
 Rockstar Games released "Grand Theft Auto V" on 17 September 2013 for PlayStation 3 and Xbox 360, on 18 November 2014 for PlayStation 4 and Xbox One, and on 14 April 2015 for Microsoft Windows, as the fifteenth entry in the "Grand Theft Auto" series.
 Development began soon after "Grand Theft Auto IV"' s release and was led by Rockstar North's core 360-person team, who collaborated with several other international Rockstar Games studios.
 The team considered the game a spiritual successor to many of their previous projects like "Red Dead Redemption" and "Max Payne 3".
 After its unexpected announcement in 2011, the game was fervently promoted with press showings, cinematic trailers, viral marketing strategies and special editions. Its release date, though subject to several delays, was widely anticipated.
Grand Theft Auto III is an open world action-adventure third-person shooter video game developed by DMA Design and published by Rockstar Games.
 It was released in October 2001 for the PlayStation 2, in May 2002 for Microsoft Windows, and in October 2003 for the Xbox.
 A remastered version of the game was released on mobile platforms in 2011, for the game's tenth anniversary.
 It is the fifth title in the "Grand Theft Auto" series, and the first main entry since 1999's "Grand Theft Auto 2".
 Set within the fictional Liberty City, based on New York City, the game follows Claude after he is left for dead and quickly becomes entangled in a world of gangs, crime and corruption.
Grand Theft Auto IV is an action-adventure video game developed by Rockstar North and published by Rockstar Games.
 It was released for the PlayStation 3 and Xbox 360 consoles on 29 April 2008, and for Microsoft Windows on 2 December 2008.
 It is the eleventh title in the "Grand Theft Auto" series, and the first main entry since 2004's "".
 Set within the fictional Liberty City (based on New York City), the single-player story follows a war veteran, Niko Bellic, and his attempts to escape his past while under pressure from loan sharks and mob bosses.
 The open world design lets players freely roam Liberty City, consisting of three main islands.
Grand Theft Auto is an action-adventure video game developed by Digital Eclipse and published by Rockstar Games for the Game Boy Advance, released on October 26, 2004.
 The game is referred to as Grand Theft Auto Advance on its title screen; the game's cover art and all promotional material refer to it as simply "Grand Theft Auto".
Grand Theft Auto: Liberty City Stories is an open world action-adventure video game developed by Rockstar Leeds in conjunction with Rockstar North and published by Rockstar Games.
 Released on 25 October 2005 for the PlayStation Portable, it is the ninth game in the "Grand Theft Auto" series and was preceded by "" and succeeded by "".
 It is a prequel to "Grand Theft Auto III".
 It was published and distributed by Capcom for the Japanese release.
 It was released on PlayStation 3 via the PlayStation Network on 2 April 2013.