Titanfall 3 is not currently in any stage of development at Respawn according to studio head Vince Zampella.
This news comes from an interview of Mr. Zampella by IGN marking the tenth anniversary of the creation of Respawn Entertainment. The interview covered both the history and future of the Respawn, which is best known for Apex: Legends as well as Star Wars Jedi: Fallen Order. Zampella also discussed Battlefield support studio DICE LA which he recently was promoted to manage in addition to Respawn.

Via Ars Technica
As for the future of the Titanfall series, according to the interview, nothing is currently being worked on aside from support for the spinoff Apex: Legends. Titanfall was the first game Respawn made after Zampella and most of the Respawn staff left Activision amid contentious disputes over the management of the Call of Duty franchise. Both core games in the franchise, Titanfall and Titanfall 2, were critically acclaimed and built a strong cult following but neither performed as well commercially as other more recent games from Respawn. The Titanfall series is apparently a favorite of the Respawn team as Zampella told IGN, “At some point, I would personally like to see some kind of Titanfall resurrection. We’ll see if I can make that happen.”
As for what the studio actually has in development currently, Respawn is working on Medal of Honor: Above and Beyond which is scheduled for release this year. The studio is also working to support Apex: Legends which recently added a new character to its roster. It is also safe to assume that there is a team at Respawn working on a follow up to Star Wars Jedi: Fallen Order despite the lack of any official announcement. EA CEO Andrew Willson has made cryptic allusions to Fallen Order being the start of a franchise and the team for that game within Respawn is currently hiring.
This all puts the Titanfall fandom in a strange position. The studio that made their favorite game is successful but that success isn’t translating into more games like the one they like.
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