Ubisoft, the publisher of all four Techland's Call of Juarez games, shut down The Cartel's servers last year and it looked like you wouldn't be able to play not only the multiplayer, but even the single-player mode after the sudden disappearance of the third chapter of the series and much better Gunslinger (which was available mostly only in the digital form) from Steam, Xbox Live, and PlayStation Store.
The French publisher has finally decided to address the sudden delisting from console and PC online storefronts. "Per the terms of agreement, Call of Juarez The Cartel and Call of Juarez Gunslinger licensing/publishing rights have reverted back to Techland, while others remain active with Ubisoft," the company's PR told GameInformer. "This is why a few titles have recently been removed from Steam, but it is our understanding that Techland is working to bring those titles back, so please feel free to reach out to Techland regarding status.”
It looks like Ubisoft is not seeking to reacquire the licenses and publishing rights involved, so the games' return to the digital stores is entirely in Techland's hands. It's understandable, considering that Ubisoft has decided to only publish the games that were developed in-house, also meaning that any future Call of Juarez games would need to find a new publisher or be released directly by Techland.