The Roy Lichtenstein Centennial Stamp was issued on April 24, 2023.
For more information see:
U.S. Postal Service Honors Roy Lichtenstein’s Pop Art on New Forever Stamps
U.S. Postal Service Honors Roy Lichtenstein With New Forever Stamps

The Roy Lichtenstein Foundation announces the first major group of art and archival Lichtenstein Centennial gifts to five museums, see:
Roy Lichtenstein Foundation Donates 186 Artworks to Five Museums Ahead of Artist’s Centennial
Roy Lichtenstein Foundation Press Release