No.
Apibioxal is 88.6% Oxalic Acid Dihydrate (which is the same form of OA that all of the other mass values use, and what those who buy "pure" OA are getting 99.6% of in the tub). For sublimation the stated dose is 2.3g of Apibioxal which is a little over 2g of Oxalic Acid Dihydrate. There can be around 0.1g of residue because of the post-heating compounds resulting from the silica and sugar which make up the other ~10% by mass of the original product.
The authorised dose is different for trickling (works out around 3.5g Apibioxal per hive maximum, depending on how many seams of bees are present and treated) but not directly relevant to this question.
I'm not sure what you mean by "weighted more" since generic and authorised OA products are sold, and dosed, by mass. 2.5g of one weighs the same as 2.5g of the other (assuming same place, time, temperature...). The authorised dose for sublimation by Apibioxal is in fact slightly less at 2.3g. Api-bioxal is probably slightly denser than generic, owing to the additives.