Product number

All of the Monster High items manufactured by Mattel itself have one or two numbers on the back of the packaging, usually in the lower right corner. These numbers are the product numbers, which Mattel assigns to its products — whether they are Monster High-related or not — so that they can be systemized. In case of two numbers, the first is the assortment number and the second the model number. In case of only one number, it alone is both. All items that have the same assortment number are part of the same assortment.

The reason product numbers are interesting is similar to why trademarks are: they tell something about the franchise's development. By default, an assortment number is followed in order by its model numbers. For instance, the first Coffin Bean assortment is BHN03 and its three dolls are assigned BHN04, BHN05, and BHN06. Changes in the assortment number under one series name sometimes indicates a change in availability or price point but just as easily it means nothing at all.

Because the product numbers by default are ordered, irregularities in the order of the product numbers indicate changes of plans up until shortly before production was started. The case of Classroom Draculaura is a prime example. The doll was assigned W2559, but was never produced, and so the dolls that hit stores were W2557, W2558, and W2560. There are no other proven cancelled dolls, but notably missing model numbers — meaning that no product, whether Monster High or not, is assigned these numbers — include T7983, T7989, and X3713, which align with Scream Uniform, Gloom Beach, and Ghouls Rule. It is, however, perfectly possible for the assigned doll to have been released anyway under a different number. The Ghouls Rule number, for instance, could have been meant to be Cleo but through miscommunication have been made X3718.

Other oddities to keep in mind when looking at product numbers is that sometimes international versions of the dolls have different ones from the USAmerican versions. N2851, the Signature assortment number in the USA, is X4603 internationally. Also, some assortments and models have two instead of one product number, proving that sometimes irregularities simply happen because of human errors. Some of the Ghoul's Alive! dolls are examples of this. And lastly, a few lines contain exactly one doll with an irregular model number. What this means is not known.