1669
March 25, 2026
Dr. Beckett responds to Mike Lach’s question about why grading companies don’t apply an MK (mark) qualifier to post-production, in-person on-card autographs. He explains PSA’s early-1990s introduction of qualifiers (OC, MC, ST, MK, PD, OF) to note manufacturing related issues, and how MK indicates extraneous markings that lower the card’s value though the technical grade reflects centering, edges, corners, and surface(!). Dr. Beckett notes that autograph collecting and card grading were once sep...