Dozens of US technology companies, including Amazon, Apple and Microsoft, have been affected by a ‘bizarre’ computer glitch, causing some companies to lose billions in market value.

According to the Guardian, a bug was triggered after a Nasdaq test was wrongly interpreted, leading to ‘uproar’ on Nasdaq stock exchanges, as Reuters, Google Finance data and Bloomberg were reported the same price at US$123.47 on trading floors.

Amazon’s shares showed an 87% drop, falling from almost US$950; Alphabet, Google’s owner, fell by 86%; followed by Apple falling by 14.3%.

It is rumoured that the stock exchanges that closed early this Monday could have been behind the glitch.

“Nasdaq is investigating the improper use of test data distributed by the unlisted trading privileges (UTP) and consumed by third parties,” a spokesman said.

“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,” he added.

Nasdaq believes the error was because of “unlisted trading privileges”, which allows exchanged stock to be traded elsewhere.

Written by Leah Alger