Wisconsin discovery of 97 rare Super Mario Bros. cartridges

A collection of 97 rare, new cartridges of the Super Mario Bros. / Duck Hunt variant for the Nintendo Entertainment System has been discovered in a warehouse in Waukesha, Wisconsin. The lot was found by shop owner Kevin Braun while sorting through old stock at his store, OnestÀ.

Identified by Kevin Braun and Jason Ganos, the 1993 variant was previously undocumented in existing catalogs. The cartridges feature multilingual back labels and different internal circuit board configurations compared to known versions. Additionally, the manuals contain a textual variation, using the phrase “maintenance or service” instead of “maintenance or repairs.” Production code 9340 indicates the lot dates to the 40th week of 1993.

The origin of the batch remains uncertain, with theories suggesting they may have been spare parts for warranty repairs, units for refurbished consoles, or components for an unreleased bundle. The items were originally intended for metal recycling but were instead preserved in storage.

Professional Sports Authenticator (PSA) has authenticated the collection. The results are unprecedented for NES cartridges, with no piece scoring below 9.6 and five cartridges receiving a perfect 10 grade. The items are expected to be listed for sale by Goldin starting in August 2026.