A CVO is Stage I straight from the factory. It has increased displacement, high flow air cleaner, and a less restrictive set of mufflers compared to a stock standard model. Ten years ago they actually said that, and the next step up calibration from stock was called the Stage I Race calibration, used with higher flow exhausts and intakes, as opposed to the stock Stage I calibration. These days they don't offer illegal "race" calibration downloads, since the EPA and CARB finally started paying a little attention.
Why the question? If you're trying to determine if the current calibration is appropriate for the bike, the dealer can definitely check to see what calibration is loaded to the ECM and compare to the calibration that came stock. If it isn't the stock map, and it isn't one of the canned maps Harley offered with the SEPST, then it will take some sleuthing to figure out exactly what you do have.
Jerry