According to Dr. Dan Laursen, all variations of the ‘DANMARK BEFRIET 5 MAJ 1945’ overprints are bogus. The variations are changed colors and inverted overprints.
This is highly controversial as they rank among the most valuable and sought after stamps from Greenland. Read Dr. Laursen’s fascinating article here.
Note that these stamps normally come with certificates by respected experts. You can say that the ‘genuineness’ thus refer to ‘genuine bogus’.
