The US tech sell-off resumed in earnest overnight, after a month-end rally in last Thursday’s session, which also marked the end of the March quarter.

Sharp declines among the US tech titans have dragged the broader NASDAQ index back into negative territory for the year, and Atlassian hasn’t been immune to the selling.

The Sydney-headquartered company is down more than 10% from its March highs. Here’s how those falls compare to the FAANG stocks (Facebook, Amazon, Apple Netflix and Google):

The selling has wiped almost $US1.9 billion from Atlassian’s market capitalisation, based on a total of 227,263,646 shares outstanding as shown on Investing.com.

So the net worth of co-founders Mike Cannon-Brookes and Scott Farquhar — who reportedly still own more than half the company — would have declined by around half that amount.

That said, Atlassian’s closing price overnight of $US53.78 still marks a gain of almost 80% from the same time last year.

The outlook for big tech stocks is getting increased attention, given they are the same companies that underpinned last year’s market rally which ultimately saw the S&P500 hit an all-time high at the end of January.

But now US President Donald Trump has picked a fight with Amazon, while analysts are predicting more headwinds for Facebook in the fallout from its Cambridge Analytica data-sharing scandal.

And it’s all happening amid the prospect of increased regulatory scrutiny, with leaders of major tech companies set to be hauled up to testify in front of US Congress.

This table shows the daily moves since Monday March 12 among the FAANG stocks plus Atlassian, one week before the allegations against Facebook wiped more than 6% from its stock price in one day:

The price action has been largely coordinated, with consistent selling offset by two rallies — last Monday after trade war fears cooled off over the prior weekend, and Thursday’s bounce heading into the Easter long weekend.

But both rallies were immediately followed by an equally sharp sell-off, with markets on edge now that the main driver of US stock market growth appears to be running out of steam.

Australia’s ASX200 — which is notably light on big tech companies — is holding up quite well in early trade given the weak US lead.

After opening 0.5% lower, a short time ago the local index was climbing back towards even for the day in morning trade.

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