X0101 EFFECT 33 LIVE 2025-04-23 16:00:00

S-4

0002005951 Smurfit Westrock plc 333-286364 0001732845 WestRock Co 333-286364-12 0001907939 WestRock MWV, LLC 333-286364-11 0001908009 WestRock RKT, LLC 333-286364-10 0001636023 WRKCo Inc. 333-286364-09 0002060630 Smurfit Kappa Treasury Unlimited Co 333-286364-08 0002060635 Smurfit Westrock Financing Designated Activity Co 333-286364-07 0002060537 Smurfit Kappa Acquisitions Unlimited Co 333-286364-06 0002060546 Smurfit Kappa Investments Ltd 333-286364-05 0002060550 Smurfit Kappa Treasury Funding Designated Activity Co 333-286364-04 0002060567 Smurfit WestRock US Holdings Corp 333-286364-03 0002061186 Smurfit Kappa Group plc 333-286364-02 0000937275 SMURFIT INTERNATIONAL B V 333-286364-01