3D Realms, independent developer of theaction franchise, is closing its doors and its employees being let go, according to multiple industry sources.News of the closure was first reported by Shacknews , with Gamasutra obtaining separate confirmation. Sources told Gamasutra the studio will be fully shut down by the end of the week.Formed over twenty years ago as Apogee Software and located in Garland, Texas, 3D Realms was privately owned and run by Scott Miller and George Broussard. It served as developer of the three maingames and as publisher of many more.For more than a decade, 3D Realms has notoriously been working on various iterations of, its sequel to the classic FPSwas announced in 1997, and saw repeated delays.In the last few years, news about the game began to emerge more frequently, and small screenshots and development tidbits were occasionally released.Recently, 3D Realms also produced the twogames by Remedy Entertainment, published Human Head Studios', and broughtto Xbox Live Arcade.Gamasutra has received a statement from Deep Silver and Apogee Software , the label recently resurrected by 3D Realms for its retro-flavored offerings.The companies state that development of, a Nintendo DS and PSP platformer compilation of, is unaffected by today's news. Development of the trilogy is being handled by Frontline Studios.In addition, Take-Two has released a statement to outlets including Shacknews , as follows: "We can confirm that our relationship with 3D Realms forwas a publishing arrangement, which did not include ongoing funds for development of the title. In addition, Take-Two continues to retain the publishing rights to."]