"It's enormous. They were the big machers. Particularly Benjamin, because he lived locally. Isaac had moved to London with his family and used to fly there and back. He ran the London office and was very prominent in north-west London circles," he said.
Gibraltar's 800-strong Jewish community was torn between offering the family private support, and the public embarrassment of the trial. As the truth emerged, backing fell away. The insider said: "It was all smoke and mirrors - a complete Ponzi scheme. They had been robbing Peter to pay Paul."
The brothers were first arrested in 2010 following the collapse of their Marrache and Co firm. Their globe-trotting lifestyles and careers representing the rich and famous - including a large number of Russian Jewish oligarchs - came to an immediate end, replaced with time spent on remand in Gibraltar's mediaeval Moorish Castle.
It took years to bring the case to court as prosecutors sifted through thousands of financial documents. The brothers launched numerous attempts to have the charges dismissed.
When the trial finally got under way last year, the Supreme Court heard evidence from dozens of witnesses, including Gibraltar's Attorney General. The hearing lasted for more than 10 months and included 47 adjournments.
Benjamin and Solomon were found guilty of two counts of conspiracy to defraud, and Isaac of one charge.
Victims included young investors, first-time home buyers, an Irish multi-millionaire, a retired teacher and a successful Czech businessman. Trial judge Sir Geoffrey Grigson said the brothers had shown a "complete lack of remorse" and "an unscrupulous desire to avoid accepting responsibility".
Benjamin was sentenced to 11 years. Solomon and Isaac - who had been living in Hampstead Garden Suburb before his arrest - were both given seven-year terms. Their co-defendant and former employee, Leanne Turnbull, was cleared of all charges.
