Actually, that's a good question. Tents invariably have a package weight and a minimum weight. Take Marmot's Nutshell ($259). It lists as a package weight five pounds, 12 ounces. But it's minimum weight is four pounds, ten ounces - more than a pound less. The difference is that the package weight includes the box the thing comes in, its stuff sack, poles, stakes, patch kits, instructions, spare parts - the whole shootin' match. The minimum weight is based on the least one might carry into the woods with that tent - the tent itself, of course, and the poles. Marmot does not include a minimum stake count in that, and stakes will easily add three to four ounces or more. But no one else includes that, either.
Anyway, it's usually the minimum weight you see in articles and advertisements - it's what we use in the Outside Magazine Buyer's Guide and most reviews. I don't think it's misleading; it's a good relative measure of one tent to another, and a pretty good absolute measure of a tent's weightiness. Of course, the wild card in this is that fabric lots and other materials used in a tent can vary. Some cynics suggest that a tent maker will rifle through 100 or so finished tents, looking for the one that through some fluke weighs two ounces less than the rest of them. Presto! That's the weight for all of them. I dunno - I suppose that sort of thing might happen. But I usually find that the weights are pretty accurate, to an ounce or two, when put to the scale test by non-company critics.