Granted, the IP address correlation isn't 100 percent accurate. Facebook can cross-check the IP address with the browser version, for example, or look at other information that's transmitted with every Web access and possibly discern among multiple individuals using the same Internet connection. But unless you've changed your IP address between the time you hit a "Like" page and the time you log into Facebook, the dots are all lined up and Facebook need only connect them.
Note that I didn't say anything about In-Private browsing, or Incognito mode. You can run in Private mode, if you like, but it won't protect you from this kind of correlation. I didn't say anything about blocking third-party cookies: Facebook doesn't have to plant a cookie on your machine in order to track you in this way -- third party or otherwise. You can block cookies till you're blue in the face but still fall into this tracking trap. I didn't even mention logging out of Facebook or closing down your browser, deleting temporary files, or shutting down your computer. Won't work.
This isn't a Facebook problem. It's simply the way the Internet works.
Google can do the same thing: It keeps track of your Google searches, correlating them with an originating IP address. When you log in to Google+, the folks at Google can compare your logged-on IP address with all of the IP addresses in their databases. Google also tracks all of those websites with DoubleClick ads. Again, the match isn't 100 percent accurate, but it's certainly good enough to prompt the Googlies to offer you a personalized ad.
Then there's Microsoft -- Bing searches, Windows Live logons ... you get the picture.
What can you do? The easiest way is to work from behind a multi-user firewall with a whole lot of Internet users sharing the same IP address. If you aren't behind a big firewall you can connect to a Virtual Private Network. Failing that, you can sometimes manually disconnect and reconnect your Internet service, and that may (or may not) reset your IP.
Most of all, you need to realize that you leave a trail behind wherever you go.
The next time someone tells you that you can can avoid Facebook lingering cookie-style problems by running Incognito, tell them how the Internet really works.
IP addresses aren't perfect identifiers, but they're close enough for advertising work.
This story, "Facebook fixes lingering cookie behavior, but that doesn't solve the problem," was originally published at InfoWorld.com. Get the first word on what the important tech news really means with the InfoWorld Tech Watch blog. For the latest developments in business technology news, follow InfoWorld.com on Twitter.