A few days after Microsoft broke away from Bungie, the original development studio behind the Halo series, the company envisioned many ways to progress with the Halo universe. One of these would have been to entrust the development of Halo 4 to Gearbox Software, the studio behind the famous Borderlands franchise.
In an interview with Ryan McCaffrey of IGN, Bonnie Ross, current developer of Halo, 343 Industries, is immersed in the possible avenues envisioned by Microsoft after Bungie's departure after Halo 3. While Microsoft planned to end the Halo series, because of Halo's ambiguous end Third, it was possible to use an outside studio to direct development on future games. From IGN:
Another possibility was that Microsoft entrusted the reins of the franchise to an external studio for development, at least for one or two more games. The pioneer Microsoft at the time was Gearbox Software, the studio responsible for the Halo PC port: Combat Evolved and the same team that later created the famous Borderlands franchise.
In the end, Ross convinced the management of Microsoft Game Studios that the development was to remain in-house and has been given the responsibility of leading Halo's future. A new internal team, 343 Industries, was created and led to the development of Halo 4 and 5.
It's hard to say how the Halo series would have been different if Gearbox had received the keys of the realm, so to speak. But that would have been an interesting turning point, of course.
343 Industries is currently working on the next entry in the Halo series, called Halo Infinite. Apart from a short teaser presented at E3 2018, little is known about the following, but Ross said that 343 Industries was learning lessons from mistakes made in previous entries while seeking to "do the well "with the series.
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