We suggest you to also create a Customer Marketing case with us so that we can work towards a resolution faster (in case the chips are not authentic). Meanwhile we will check the top markings and let you know.
The marking is ok for the chips. The generalized format for these parts is
Line1 – pppp stands for marketing part number
Line2 – yyww is yeas and work week
Line3 – rr is BE part rev
Line3- ff is FAB location
Line3- b is space
Line4- lll is CYP and nnnnnn lot #