The satoshi sealed within this card originates from the first bitcoin of Block 9, mined by Satoshi Nakamoto on January 9, 2009. This block is historically significant as the oldest whose mining reward was ever spent. Sats from the first bitcoin are numbered between 45,000,000,000 and 45,099,999,999, and this one is in the very early range. Holding this Proof of Sats card means holding a fragment of the first bitcoin.