Oikos for twoMr. Tidbit thought he had completed his exploration of the topic of pricey Greek yogurt with this simple declaration: It's yogurt with some of the whey drained off. So he had almost stopped glancing at the plethora of Greek yogurt choices in the dairy aisle when he noticed Oikos Greek yogurt with caramel on the bottom. He had thought the choices for yogurt bottom-feeders were all of the sweetened-fruit variety. Or maybe honey. Not caramel -- or, right next to it, chocolate.

Those flavors were present only in four-packs. And, now that he focused the laser-like beam of his intellect on the topic, those four-packs, and some single-serve Oikos tubs alongside them, didn't look like the much larger collection of dark-blue tubs of Oikos.

Wait: There are two brands of yogurt called Oikos! The larger one, in the dark blue tubs, is Dannon Oikos. The other, including the caramel- and chocolate-bottomed varieties, is Stonyfield organic Oikos. On the Dannon tubs, the word Oikos is followed by ®, the circled-R symbol of a registered trademark. On the Stonyfield package, the word is followed by , the symbol for "trademark."

Mr. Tidbit is assured that the "registered" mark used by Dannon is the much stronger of the two: It indicates that the name has been officially registered with the U.S. Patent and Trademark Office, whereas the "trademark" symbol on the Stonyfield package essentially can be used by anybody to indicate that a trademark might be sought.

So has Mr. Tidbit stumbled upon the opening shots of an Oikos war? Is giant Dannon, which has registered the Oikos trademark, about to sue the organic pants off little Stonyfield Farms?

No, friends. It turns out that French giant Group Dannone owns both of them. But vive la difference: At one store, where 5.3-ounce tubs of Dannon's Oikos cost $1.22 (23 cents per ounce), the same size tubs of Stonyfield's organic Oikos are $2.39 (45 cents per ounce).

And a reminder: At that store, 6-ounce tubs of regular, less-drained, Dannon yogurt are just 89 cents -- 15 cents per ounce.

AL SICHERMAN