Error card

In the trading card collecting hobby, an error card is a card that shows incorrect information or some other unintended flaw. It can contain a mistake, such as a misspelling or a photo of someone other than the athlete named on the card. Depending on whether the manufacturer noticed the problem while the cards were still being produced, a card may exist in both correct and incorrect versions. If the correction is made sufficiently early in the print run, the error card may be significantly rarer and more valuable than the corrected version. However, the opposite may be true if the error is corrected late in the printing cycle, resulting in a smaller population of the corrected version of the card compared to the error version.

If the manufacturer never made a correction, the card is considered an "uncorrected error". Often, however, "error card" is used in a more limited sense, meaning only those cards where variant versions exist.

One example of "variations" happened in the 1959 and 1960 Topps baseball sets. Certain cards were printed on two different types of cardstock; one produced a white back, and the other a darker gray. The photographs and information on the cards themselves were not in error. The result was that said cards occur in two variations, based on the back color.

The Bowman cards of the 1950s contain two notable errors. The first was not technically an error, but nonetheless resulted in an anomaly in the 1954 Bowman set. The set featured Ted Williams as card number 66. Shortly after the set was released, Williams signed an exclusive contract with Topps, Bowman's primary competitor. Topps featured Williams as the first and last cards in their set that year. Now barred from using Williams's picture and name, Bowman substituted Williams' teammate Jimmy Piersall as card number 66 in all subsequent printings, duplicating the front and back of Piersall's other card in the series, number 210.

The next year, in their last set before selling out to Topps, Bowman "flipped" the backs of two pairs of cards. Brothers Milt Bolling of the Red Sox and Frank Bolling of the Tigers and pitchers Don Johnson of the Orioles and Ernie Johnson of the Braves were originally issued with their counterparts' card backs. Bowman corrected the error and issued cards with the correct backs.

In its 1956 set, Topps issued six team cards, the Cubs, Reds, Orioles, Indians, Braves and Phillies, in three different versions. The different cards are commonly referred to by collectors as the "dated", "undated" and "centered" cards. The first release showed a team picture, obviously taken the year before and correctly labeled as "1955 Chicago Cubs, "1955 Cincinnati Reds" and so on. For some reason, perhaps because it was confusing to have a card labeled "1955" in a 1956 set, Topps reprinted these cards, blacking out the space where the date had appeared. This resulted in the team name being off-center in the black box where it appeared. Topps finally issued a third version of all six cards with the team name centered in the box.

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Wikipedia