Alphabet (GOOG, GOOGL)

Shares in tech giant Alphabet closed Monday's session 2.5% in the red, after a US judge on Monday ordered Alphabet's Google to restructure its app store to give users more options as part of a lawsuit with Epic Games.

US district judge James Donato ruled that for three years Google must open its Play store up to Android apps made by competitors.

Lee-Anne Mulholland, vice president of regulatory affairs at Google said in a statement that the company would appeal the verdict. She said that the "changes would put consumers’ privacy and security at risk, make it harder for developers to promote their apps, and reduce competition on devices".

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Separately, Google is also about to find out what the Department of Justice believes should be done to dismantle the tech giant’s dominance of the online search market.

Prosecutors are expected to submit a document as early as Tuesday in federal court outlining potential remedies after successfully arguing in a landmark trial that Google acted as an illegal monopoly.

Shares in Alphabet were little changed in pre-market trading on Tuesday morning.

Amazon (AMZN)

Another US technology company in the red on Monday was Amazon, which closed the previous session 3% down.

This came after Wells Fargo downgraded the company's shares from an overweight to equal weight, lowering the price target to $183 from $225.

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Wells Fargo analyst Ken Gawrelski cited challenges such as rising competition from Walmart (WMT), as well as moderating contribution from its ad business to operating income, and high costs linked to its satellite broadband project.

"Keeping these headwinds in context, Amazon remains a margin expansion story, just likely a more moderate margin expansion pace than the market expects," Gawrelski wrote.

Amazon shares tumbled back in August after the retail and cloud giant offered a quarterly forecast that fell short of expectations.

Nvidia (NVDA)

The chipmaker was the only one of the "Magnificent Seven" group of stocks to have closed Monday's session in the green, up 2.2%.

In addition to Nvidia, Alphabet and Amazon, this group of tech stocks also includes Apple (AAPL), Microsoft (MSFT), Meta Platforms (META) and Tesla (TSLA).

The rise in Nvidia shares on Monday lifted its market capitalisation to $3.13tn, seeing the chipmaker overtake Microsoft as the world's second most valuable company. Microsoft closed the previous session with a market valuation of $3.04tn.

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Meanwhile, senior executives at Taiwan's Foxconn (2354.TW), the world's largest contract electronic manufacturer, reportedly said on Tuesday that the company was building a production plant in Mexico for Nvidia's GB200 "superchips".

"We're building the largest GB200 production facility on the planet," said Benjamin Ting, Foxconn senior vice president for the cloud enterprise solutions business group, according to a Reuters report.

Shares jumped last week, after Nvidia CEO Jensen Huang said in an interview with CNBC that demand for the company's next generation Blackwell chips has been "insane".

Super Micro Computer (SMCI)

Shares in Super Micro Computer surged nearly 16% on Monday, after the company said it's shipping more than 100,000 graphics processing units (GPUs) used for artificial intelligence per quarter.

Super Micro, which provides servers and data storage systems, also unveiled a suite of liquid cooling products in an announcement on Monday.

These liquid cooling products aim to keep GPUs and central processing units (CPUs) working at a certain temperature so they can operate efficiently, given the heat generated by the power used by servers.

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Charles Liang, CEO and president of Super Micro, said the company's solutions were now "cooling massive, state-of-the-art AI factories, reducing costs and improving performance".

Shares in Super Micro underwent a 10-for-1 stock split last week, a trend which has been seen among a number of companies this year.

The company's shares have been under pressure recently following reports that the US Department of Justice is investigating the company over alleged accounting irregularities.

Vistry (VTY.L)

In the UK, housebuilder Vistry plunged nearly 29% on Tuesday morning, after the company issued a profit warning.

Vistry said in a trading update on Tuesday that it expected adjusted profit before tax for the 2024 fiscal year to be £80m ($104.7m) lower than previous anticipated, at around £350m. The housebuilder said it expected adjusted profit before tax to then be £30m lower in 2025 and £5m in 2026.

The fall in forecasted pre-tax profits was that the company had discovered that the cost projections for to complete some of the developments in its south division had been understated by around 10%.

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Vistry said: "We believe the issues are confined to the south division and changes to the management team in the division are underway. We are commencing an independent review to fully ascertain the causes."

Russ Mould, investment director at AJ Bell, said: “Vistry had been quietly eking out a strong reputation with the market over recent years but today’s news has done a lot of damage to its credibility with investors.

“The scale of the understatement of build costs in its south division is jaw-dropping and it’s not a surprise to see that changes in the management of that division are underway."

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