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A Tom Brady card numbered 1 of 1, meaning it is the only one of its kind, sold at an auction Thursday for $396,000. As it turns out, it is not the only one of its kind.

A 2000 Fleer Showcase Masterpiece Brady rookie card, graded 8.5 NM-MT+ by Beckett Grading Services, sold with collectibles marketplace PWCC, but an exact one graded by PSA exists as well. 

Fleer Showcase confirmed that card manufacturers printed multiple 1-of-1 cards while working on production. The duplicate cards were not meant to leave the factory they were made in, but clearly some did.

PWCC found the Brady 1-of-1 card, but an anonymous person went to them with another rookie card labeled "The Only 1 of 1 Masterpiece." The card is still in their possession and not for sale.

Both the BGS-graded card and the PSA-graded card are both believed to be authentic. The person who purchased the Beckett-graded 1-of-1 will get a letter of authenticity. 

The former owner of the Beckett-graded version said they bought the card on eBay for about $2,000 in 2005. The card said Brady is known for his "poise [and production], especially in the big games."

In the 1990s, the sports-card market went bankrupt, and one result of this was not knowing how many of each card were produced. The first 1-of-1 card was produced in the late 1990s.