He is the chairman of Platinum Studios, an entertainment company that controls a library of comic-book characters and adapts them for film, television and other media.
Rosenberg began his career in the comic-book industry at age 13 when he started a mail order company[3] called Direct Comics.
During his time at Malibu, Rosenberg led comic spin-offs into toys, television, and feature films, including the billion-dollar film and television franchise Men in Black,[3] based on the Marvel/Malibu comic The Men in Black by Lowell Cunningham.
[16] By the middle of 1993, Image's financial situation was secure enough to publish its titles independently, and per the agreed upon distribution agreement with Malibu, ventured out on its own.
[17] During this period, Rosenberg also worked with Adobe Photoshop software to develop the then-leading standard for the computer coloring of comic books.
[21] Rosenberg left Marvel in January 1997, and purchased half of Platinum Studios from European rights agent Ervin Rustemagić.
[21] Platinum produces based on two distinctive categories: Those from the "Macroverse Bible," a multi-thousand-page bible of related comic characters created by Rosenberg,[18] including titles such as Cowboys & Aliens,[3] and properties acquired from other companies or creators such as Dylan Dog: Dead of Night and Jeremiah.