Or the box I buy in Canada may be from a different supplier than the box you buy in some other country. The box you buy today may have a different paper in it than the box I bought last year. As someone else pointed out, they may change suppliers from time to time that sort of thing is quite common for store-brand products in many industries. Now, that's not to say that all Staples papers are bad. I have several others that rarely see any sort of light, only being brought out to be looked at, and they've held up well. Let me put it this way: I have a photo on HP paper that is several years old and gets hit briefly with late-day sunlight pretty much any day it's sunny (plus normal interior lighting), and it looks very good I have several pictures on Staples papers that are two or thee years old and never exposed to sunlight (only normal interior lighting) and have faded very badly.

One caution: I've used a couple of Staples papers (gloss and satin) and have had poor display life from my HP Photosmart 7960 using genuine HP ink cartridges.

Staples photo supreme paper archival