Why did Apple, Amazon, Google stocks crash to the same price today?

Nasdaq announced Monday night that "improperly" processed test data by third-party vendors was to blame for a glitch that made it appear as if Apple, Amazon and Google stocks were crashing.

Popular stock sites such as MacOS widgets, Google Finance and Yahoo Finance appeared to show stock prices for Apple, Google, Amazon and Microsoft all at 123.47 on Monday evening. For Amazon, that would mean shares finished the day down 87 percent when in actuality AMZ finished the day down 1.5 percent at $953.66.

Nasdaq said in a statement that "certain third parties improperly propagated test data that was distributed as part of the normal evening test procedures."

"For July 3, 2017, all production data was completed by 5:16 PM as expected per the early close of the markets," the statement continued. "Any data messages received post 5:16 PM should be deemed as test data and purged from direct data recipient's databases. UTP (Unlisted Trading Privileges) is asking all third parties to revert to Nasdaq Official Closing Prices effective at 5:16 PM."

According to a report on MarketWatch.com, traffic on its stock pages soared as concerned investors checked to see what happened in after-hours trading.

The error could have occurred because of Monday's half-day of trading ahead of the July Fourth holiday, the Financial Times reported.

In a 10 p.m. tweet, Nasdaq said it's "working with third party vendors to resolve the matter as quickly as possible."

Alex Napoliello may be reached at anapoliello@njadvancemedia.com. Follow him on Twitter @alexnapoNJ. Find NJ.com on Facebook.

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