Inventor

JOHNSON DAVID NIEL

US3 patents

Patents

3 patents

US11263503B2Mar 1, 2022

Signature-based unique identifier

HALLMARK CARDS4 citations80

US11900194B2Feb 13, 2024

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HALLMARK CARDS2 citations69

US12288113B2Apr 29, 2025

Signature-based unique identifier

HALLMARK CARDS0 citations59