This is an interesting question. I contacted the folks Pampers and Huggies to get to the "bottom" of this. Pampers let me know that their diapers do not have an expiration date. They said that the only thing that may happen over time is a possible discoloration to a light yellow. But, they said the performance does not go down. Huggies responded that there is no shelf life or expiration date on their diapers.
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