Ubisoft's version of the online pass, designed to gate people out of online play unless they purchase a game new, is officially dead. The publisher has confirmed this on their blog, noting that due to customer complaints, you will no longer need an online pass for Assassin's Creed IV (which was shipped with one in the case), or any other game for the foreseeable future. Ubisoft put it rather simply, noting, "the Uplay Passport will not be a part of any future Ubisoft games."
You have to give it to Ubisoft -- although they did use this scheme among other ill-fated anti-consumer practices (draconian PC DRM), eventually, they relented. The online pass, or "Project 10 Dollar" is officially a bust. Sony was the first major console manufacturer to implement it in all of its first party games, but with the recent PS4 FAQ, they've since confirmed that they won't be supporting the practice anymore. Many publishers have already eliminated passes, and now, you can add Ubisoft to that list. I really hope this is the last time I have to add the "online pass" tag to a story.
Again, this is the Ubisoft Uplay Passport, so the Uplay online store and the Uplay login system will keep on truckin'.