| D-Rockets | Japan | October 7, 2008 | 1 | — |
| D-techno | — | — | 1 | 1 |
| D3 Publisher | United States | February 5, 1992 | — | 113 |
| D3arts.cz | Czech Republic | 2008 | 1 | 1 |
| Daedalic Entertainment | Germany | 2007 | 10 | 28 |
| Daewon Media | South Korea | 1973 | — | 1 |
| Dalcom Soft | South Korea | March 2014 | 1 | — |
| DAMAGE STATE | United Kingdom | — | 1 | 1 |
| Dancing Dots | France | 2006 | 4 | — |
| Dangen Entertainment | Japan | 2017 | — | 10 |
| Danger Close Games | United States | 1995 | 13 | — |
| DangerousBob Studio | United States | — | 3 | 2 |
| Dark Energy Digital | United Kingdom | 1998 | 2 | 1 |
| Darkania Works | Romania | — | 2 | 1 |
| DarkArts Studios | South Africa | — | 1 | 1 |
| Darkflow Software | Latvia | — | 1 | — |
| Darkside Game Studios | United States | 2008 | 1 | — |
| Darkworks | France | 1998 | 1 | — |
| Darril Arts | Italy | — | — | 1 |
| Dassault Systèmes | Australia | 1981 | — | — |
| Data Design Interactive | United Kingdom | 1983 | 14 | 3 |
| Data East | Japan | April 20, 1976 | 23 | 21 |
| DATA WEST | Japan | May 26, 1986 | 3 | 3 |
| Datam Polystar | Japan | May 30, 1990 | 3 | 8 |
| Datamost | — | 1981 | — | 3 |
| Datasoft | United States | June 12, 1980 | 2 | 2 |
| Davilex | Netherlands | 1987 | 1 | 1 |
| Davilex Games | Netherlands | 1997 | 62 | 26 |
| Daybreak Game Company | United States | 1995 | 6 | 8 |
| Daydream Software | — | 1994 | 1 | 1 |
| DC Comics | United States | 1977 | — | 1 |
| DC Studios | United States | 1999 | 2 | — |
| DCF Studios | Brazil | — | 1 | 1 |
| Dead Drop Studios | United States | — | 3 | 3 |
| Deadline Games | Denmark | 1996 | 2 | — |
| Deadpan Games | United Kingdom | — | 1 | — |
| Dear Villagers | France | — | 1 | 14 |
| Debonosu Works | Japan | — | 2 | — |
| Deck13 Interactive | Germany | 2001 | 5 | 3 |
| Deconstructeam | — | 2012 | 2 | — |
| Deep Silver | Germany | 2002 | — | 52 |
| Deep Silver Dambuster Studios | United Kingdom | 2014 | 2 | — |
| Deep Silver Vienna | Austria | 2007 | — | 1 |
| Deepnight Games | France | June 8, 2020 | 1 | 1 |
| Defiant Development | Australia | — | 2 | 2 |
| Defrost Games | Sweden | 2010 | 1 | — |
| Degica | Japan | June 13, 2005 | 1 | 4 |
| Dejobaan Games | United States | 1999 | 1 | 1 |
| Delightworks | Japan | — | — | 1 |
| Delphine Software International | France | 1988 | 6 | — |
| Delta 4 | United Kingdom | 1984 | 2 | — |
| Demonware | Ireland | 2003 | 1 | — |
| DeNA | Japan | March 1999 | 6 | 1 |
| Denda Games | Netherlands | 2007 | — | 7 |
| Denki | United Kingdom | 2000 | 1 | — |
| Dennaton Games | Sweden | 2012 | 2 | — |
| Design Factory | Japan | April 2, 2001 | 12 | — |
| Destination Software Inc. | United States | 2001 | — | 2 |
| Destineer | United States | 2001 | 1 | 3 |
| Destructive Creations | Poland | 2014 | 2 | 2 |
| Detach Entertainment | Germany | 2019 | 1 | 1 |
| Dev4Play | Poland | — | — | 1 |
| Development Studio | Sweden | 1995 | 14 | — |
| Devespresso Games | South Korea | 2014 | 4 | 1 |
| DevilishGames | Spain | 1998 | 1 | — |
| Devolver Digital | United States | 2009 | — | 89 |
| Devsisters | South Korea | 2007 | 1 | 1 |
| DICE | Sweden | May 1992 | 30 | — |
| Dico | Japan | 2011 | 1 | — |
| Different Tales | — | June 2018 | 1 | — |
| Digerati | United States | — | — | 28 |
| DigiCube | Japan | February 6, 1996 | — | 3 |
| DigiPen Institute of Technology | United States | 1988 | — | 52 |
| Digital Chocolate | United States | 2003 | 1 | 1 |
| Digital Continue | United States | 2016 | 2 | 1 |
| Digital Eel | United States | 2001 | 1 | 1 |
| Digital Extremes | Canada | 1993 | 4 | 1 |
| Digital Gods | Croatia | — | 1 | 1 |
| Digital Happiness | Indonesia | 2013 | 4 | 2 |
| Digital Jesters | United Kingdom | September 2003 | — | 2 |
| Digital Kingdom | Switzerland | 2013 | 1 | — |
| Digital Legends | Spain | 2001 | 3 | 1 |
| Digital Pictures | United States | 1991 | — | — |
| Digital Praise | United States | — | 1 | 1 |
| Digital Reality | United States | 1991 | 2 | — |
| Digital Touch | South Korea | — | — | 3 |
| DigiTales Interactive | Germany | March 11, 2019 | 1 | — |
| Digitality Games | Portugal | — | 1 | — |
| Digitalmindsoft | Germany | July 2006 | 3 | — |
| Dimps | Japan | March 6, 2000 | 40 | — |
| Dinamic Multimedia | Spain | 1993 | 5 | 2 |
| Dinamic Software | Spain | 1984 | 2 | 2 |
| Dingo Inc. | Japan | 1998 | 4 | — |
| Dionous Games | Cyprus | July 10, 2020 | 1 | 2 |
| Dire Wolf Digital | United States | — | 4 | 3 |
| Discovery | Japan | — | 1 | 1 |
| Disney Interactive Studios | United States | December 5, 1994 | 7 | 67 |
| Disney Mobile | United States | 2000 | 1 | 1 |
| Disruptor Beam | United States | 2010 | 1 | 1 |
| Distinctive Software | Canada | 1982 | 8 | 1 |
| DMM.com | Japan | November 17, 1999 | 1 | 4 |
| Doinksoft | United States | 2018 | 2 | — |
| Dolores Entertainment | Spain | October 2010 | 2 | 6 |
| Domark Software | United Kingdom | 1983 | 1 | 8 |
| Don’t Nod | France | 2008 | 6 | 3 |
| Double Dagger Studio | United States | — | 1 | 1 |
| Double Eleven | United Kingdom | 2009 | 2 | 2 |
| Double Fine | United States | July 2000 | 6 | 2 |
| Double Helix Games | United States | 2007 | 4 | — |
| Double Stallion | Canada | 2013 | 3 | 1 |
| Doublesix | United Kingdom | 2007 | 1 | — |
| Douze Dixièmes | France | March 30, 2017 | 1 | — |
| Dovetail Games | United Kingdom | 2008 | 11 | 8 |
| DQ Team | Moldova | — | 1 | 1 |
| Dragami Games | Japan | May 13, 2022 | 1 | — |
| Drageus Games | Poland | — | 3 | 7 |
| Drago Entertainment | Poland | 1998 | 3 | — |
| Dragonfly | South Korea | February 1995 | 1 | — |
| Drakhar Studio | Spain | — | 3 | — |
| Drakkar Dev | Italy | 2010 | 2 | — |
| Draknek Limited | United Kingdom | February 4, 2014 | 1 | 1 |
| Dramatic Create | Japan | — | 1 | 7 |
| Dramatic Labs | United States | — | 1 | 1 |
| Draw Distance | — | 2009 | 4 | 3 |
| DreadXP | — | 2020 | — | 11 |
| Dream Games | Turkey | 2019 | 1 | 1 |
| Dream Oni | United Kingdom | August 12, 2019 | 1 | — |
| Dream-Up | France | — | 6 | 6 |
| DreamCatcher Interactive | Canada | 1996 | — | 29 |
| DreamFactory | Japan | 1995 | 5 | — |
| DreamRift | United States | 2009 | 1 | — |
| Dreams Uncorporated | Colombia | — | 1 | — |
| DreamStorm Studios | Poland | — | 1 | — |
| DreamWorks | United States | October 12, 1994 | — | 1 |
| Dreamworks Interactive | — | 1995 | 1 | — |
| Drifter | United States | 2016 | 1 | 1 |
| Drinkbox Studios | Canada | 2008 | 3 | 3 |
| Driver-Inter, Ltd. | Russia | 1991 | 2 | — |
| Drop Bear Bytes | Australia | January 30, 2019 | 1 | — |
| DROsoft | Spain | — | — | 1 |
| Dry Cactus | New Zealand | — | 3 | 3 |
| DTP entertainment | Germany | 1995 | — | 9 |
| Duality Games | Poland | — | 3 | 2 |
| Dumativa | Brazil | 2012 | 2 | 1 |
| Duoyi Network | People's Republic of China | — | 1 | — |
| Dwango | Japan | August 6, 1997 | 1 | — |
| Dynamic Games | Brazil | 2004 | 1 | 1 |