Advisers with clients exposed to boiler room brokerage Sky Capital have begun enquiries into compensation, IFAonline understands.
Six directors of the firm were convicted in July 2011 of a $140m (£89m) fraud by a US court.
The New York Attorney's office said that former CEO Ross Mandell and senior broker Adam Harrington were "masters of deception who had no qualms about lying to investors, manipulating stock prices, and using dubious trading practices to enrich themselves at the expense of their victims."
The pair, along with four co-defendants, made misleading statements to inflate the broker's share price, and used the funds to pay commissions to brokers disguised as bonuses.
Despite its US base, the majority of victims are believed to be British. Around 400 UK investors parted with $110m (£70m), an average of £175,000 each.
Francesca Gandolfi, an adviser at MPL Wealth Management, said one of her clients had been "speaking to the FSA" about his options.
However, she added it remained unclear whether the compensation burden would fall on the Financial Services Compensation Scheme (FSCS), or on regulators in the US.
Joseph Eyre, a spokesperson on financial crime for the FSA, said a US-based firm would be "unlikely" to fall under the FSCS's remit.
However, the firm's UK arm, Sky Capital UK Ltd, was regulated by the FSA between 2001 and 2008. It is listed as being in default by the FSCS, meaning any claim brought in the UK would be paid for by the FSCS, possibly in the form of an adviser levy.
Otherwise, the burden would fall on a US body, the Securities Investor Protection Corporation (SIPC), which handles cases involving broker firms, including the recent collapse of MF Global.
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