British pension and ISA holders could be more exposed to Nvidia’s deepening spy scandal than they realise, with investment experts warning that millions of savers are heavily reliant on a handful of US tech giants.

The world’s most valuable chipmaker shed around $190bn (£145bn) in market value on Monday after chief executive Jensen Huang admitted to an affair with a woman suspected of working for Chinese intelligence, triggering an FBI investigation and a shareholder lawsuit.

Jason Hollands, managing director at Evelyn Partners’ Bestinvest, warned that the fallout could reach British savers who have never directly invested in Nvidia.

“The wider question for investors is whether their overall portfolio is too dependent on a small number of large technology companies,” he told City AM.

“For every £100 invested in an S&P 500 Index fund, Nvidia currently represents around £7.”

The warning exposes the extent to which British retirement savings have become tied to America’s AI boom.

Around 45 per cent of assets held in British pension schemes are invested in US shares, according to investment bank Panmure Liberum, leaving savers exposed to Wall Street’s biggest technology companies.

Nvidia alone accounts for around seven per cent of the S&P 500, while the growing popularity of passive investing means millions of Britons hold indirect stakes through workplace pensions, stocks and shares ISAs and global tracker funds.

Even funds marketed as globally diversified can be heavily weighted towards American technology companies, with the US accounting for well over half of the MSCI World Index.

“A tracker may hold hundreds of companies, but market-cap weighting can still leave it concentrated in a handful of names,” Hollands said.

The risks are particularly acute for defined contribution pension holders, whose retirement savings fluctuate with financial markets, rather than defined benefit members receiving a guaranteed retirement income.

Nvidia shares closed 4.3 per cent lower on Monday, despite the Nasdaq 100 rallying 3.4 per cent, as investors weighed the potential implications for Huang’s leadership.

The scandal has also erupted amid a wider sell-off in AI stocks, with investors questioning whether the hundreds of billions being poured into data centres will deliver sufficient returns.

Hollands said Huang’s role in transforming Nvidia into a multi-trillion-dollar business had brought a fresh concern into focus.

“Jensen Huang has been closely associated with Nvidia’s success, so uncertainty around his position brings a key-person risk into focus,” he said.

Nvidia faces shareholder lawsuit

The scandal has meanwhile spilled into the courts, with Nvidia and Huang facing a proposed shareholder class action filed in California on Monday.

The complaint, brought by investor Mark Kistenmacher, accuses the company of misleading shareholders by failing to disclose Huang’s relationship with Alice Huang, a former executive at Singapore-based data centre operator Megaspeed.

US authorities reportedly suspect Alice Huang of links to Chinese intelligence, allegations Beijing has rejected.

Huang apologised to employees on Sunday for being unfaithful to his wife, while Nvidia’s board launched an independent investigation into whether he had been targeted by a foreign intelligence operation.

Donald Trump subsequently confirmed that the FBI was examining the matter, although he defended Huang after speaking to him personally.

Nvidia’s board said it had no reason to believe company secrets or US national security had been compromised and expressed confidence in its chief executive.

“What matters is whether shareholders have suffered loss due to Nvidia failing to disclose material information, particularly given the sensitivities surrounding China, AI chips and US export controls,” Lorraine Lanceley, partner in commercial and securities litigation at Stewarts, told City AM.

She said lawyers would scrutinise what Nvidia’s board knew, when it knew it and whether material information had been withheld from investors.

But she cautioned that there remained “a considerable distance between reputational controversy and proving actionable shareholder claims”.