Popular finance websites, including Google Finance, Yahoo Finance and Bloomberg, have mistakenly shown a crash in Amazon.com Inc. and Apple Inc. stocks Monday evening.
The mistakes have prompted widespread concern among investors as third-party providers began spreading the test data as real.
Google Finance showed Amazon shares down by 87.24 percent to $123.47, while Yahoo Finance said that the online retail giant was down by 74.33 percent to $248.49 when Amazon had only lost 1.48 percent.
Similarly, Google Finance and Yahoo Finance said that Apple Inc. shares were down 14%, also to $123.47, instead of its actual 0.4 percent loss to $143.50.
Meanwhile, the same test data showed eBay Inc., Mattel Inc. and Microsoft Corp. shares soaring 253 percent, 473 percent and 79 percent, respectively.
The mistakes took place due to an error in the world's second-largest stock exchange Nasdaq's computers. The company blamed third-party data providers.
"As part of its normal process, the UTP distributed test data and certain third parties improperly propagated the data. Nasdaq is working with third-party vendors to resolve the matter," a Nasdaq spokesperson was quoted as saying by MarketWatch.
The actual prices of the stocks were not affected and no trades were completed at that price, a Nasdaq spokesman confirmed.