The Financial Services Authority (FSA) has referred Catalyst Investment Group, the UK marketing and distribution agent for ARM Asset Backed Securities, to its enforcement and financial crime division, according to reports.
The Financial Times reports the London-based group is being investigated over sales of the bonds in 2009 and 2010.
Catalyst said it was confident the FSA's investigation would not find wrongdoing.
Catalyst was the UK marketing and distribution agent for ARM Asset Backed Securities, a special purpose vehicle based in Luxembourg, whose assets were frozen by the Luxembourg authorities in August 2011.
The country's financial regulator took the action after refusing to grant ARM a licence to issue the bonds there, a decision ARM is contesting.
The FSA has previously taken action against Catalyst.
In August 2010, it withdrew permission for the group to distribute the bonds in the UK, saying the company had continued to accept some £12.5m from investors after ARM had been instructed to stop issuing the securities in November 2009.
In a supervisory notice, published in September 2011, the FSA said this particular aspect of Catalyst's business "presents a risk to consumers" and that investors' money had "not been invested in the way investors would have expected".
More than 2,000 UK residents had invested an estimated £75m in the income and capital growth bonds between 2006 and 2010.
Catalyst Investment Group said it had "retained legal services in connection with the FSA's investigation" and that it had challenged the reasons for the FSA's supervisory notice.
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