Darren Flood found "high net worth" investors to be ripped off and his fellow fraudsters played up his ties to the Manchester United football legend to fleece pensioners of savings.
Flood - the former husband of Spice Girl Victoria Beckham's sister - was a director of The Commodities Link, which cold-called the elderly to sell them worthless “rare earth metals”.
He was sentenced alongside five others at Kingston Crown Court on Friday for conspiracy to commit fraud by false representation.
Two dozen victims lost £800,000, and one potential target was the dad of former Chelsea midfielder Joe Cole.
There is no suggestion the Beckhams knew anything about the scam or about any use of the Beckham name.
Flood, 40, of Hertford, was convicted of fraud after a 10-week trial at Kingston Crown Court. He owned almost a quarter of The Commodities Link but quit after almost 10 months with the company.
Deputy circuit judge Michael Carroll, addressing Flood and the others, said the investment scheme he was involved in was "fraudulent from the outset".
He told the group: "This must have been known to you once you became intimately involved in the running of the company or played a part in it."
Flood was part of the business alongside his half brother Jonathan Docker and their cousin Gennaro Fiorentino, who played "the leading role", the court heard.
Victims were encouraged to buy “rare earth” metals which are mainly used to make tech products with the promise of big profits but paid up to 200 times over the odds.
They invested more than £800,000 - paying up to 200 times more than the original purchase price - between April 2012 and August 2014, but the materials were practically worthless.
A co-accused "made great play" of Flood's link to the Beckhams.
But Joanna Hardy, representing Flood, told the sentencing hearing her client had never used the link himself and had no contact with any customers in his role as director.
She said he "has the accident of love to blame for his link to the Beckham family".
Among the fraud's 24 victims were a widower, a retired policeman and a multiple sclerosis sufferer who complained that a telephone sales agent became abusive when he refused to pay more money.
One victim, Peter John Harris, told the trial he was cold-called by a man claiming to be named Paul Roberts, an alias used by Paul Muldoon, 34, who talked up the Becks link.
Mr Harris, who lost £100,000 in the scheme, said: “I don’t think he mentioned a great deal about the company itself.
“He did make a play about his experience in the marketplace and that of the partners.
“He also, even at that early stage, made great play about Darren Flood being involved as a director.”
Stephen Shay, prosecuting, asked: “What did he say about Darren Flood?”
Mr Harris said: “That he was the brother-in-law of David Beckham, which I suppose was supposed to give me confidence in the company.”
Mr Shay added: “He, Paul Roberts, made great play of Darren Flood being David Beckham’s brother in law.”
Muldoon admitted his involvement in the fraud before the trial.
Flood was responsible for marketing and branding as set out in a “roles and responsibilities” PowerPoint uncovered by police.
He received more than £26,000 from the company for “media and advertising work” and joined as a director in June 2012 opening its two bank accounts with Coutts bank later that year.
But in company documents he was accused by colleagues of not performing on “any level” other than to “extract expenses."
Flood was a director of the company between June 2012 and April 2013 and “tensions” with colleagues were revealed in several documents uncovered by detectives.
One, titled “TCL requirements”, said: “Jonny and Darren need to talk with high net worth clients, people, potential customers that you know.
“Since June we have been talking about Joe Cole’s dad.”
The document, which was meant for co-defendant Jonathan Docker, 32, who was also convicted, said the company’s “output is terrible”.
The document stated: “Darren has not performed on any level other than to charge money to the business and extract expenses.
“He got a bank account but this could have been done with any high street bank.
“Darren threatens to leave and close the bank accounts. This is a common threat and makes progressing the business very difficult.”
The Commodities Link, which had rented offices in London's Canary Wharf, was “wound up” by the High Court on August 29, 2014.
The company also edited negative comments from news articles about rare earth elements from China to trick potential investors.
Another victim, Mavis Wright, said she was wined and dined by Muldoon, who convinced her to hand over £41,000 using the name Paul Roberts.
She said: “I’m normally quite acute to this sort of thing but they seemed very convincing and with all the documents they sent, they reeled me in further.
“At no point did I ever suspect I was going to lose all the money I had given them.
“When we had lunch we never discussed anything to do with the investment or my money which I thought was strange - we were only with him for a few hours.
“All during this time I had no idea whatsoever that this was a scam.”
Ms Hardy, in mitigation, told the sentencing hearing: "Mr Flood has the accident of love to blame for his link to the Beckham family.
"He happened to fall in love with a lady who happened to be the sister of someone who happened to be a famous pop star.
"The evidence in this case was that it was other defendants who used the link to perpetuate their representations to the victims.
"There is not a shred of evidence that Mr Flood ever capitalised on that link.
"The only time (the name was mentioned) was when he asked employees to sign a non-disclosure agreement.
"He did not want to promote that link."
Flood, Docker, Fiorentino, 38, Mark Whitehead, 60, and Vikki King, 39, had denied conspiracy to commit fraud by false representation but were convicted by a jury in November.
Muldoon and Stephen Todd, 37, pleaded guilty to the one count of fraud by false representation at an earlier hearing.
Ike Obiamiwe, 56, and Daniel Jordan, 35, were convicted of money laundering from the alleged fraud.
Fiorentino played "the leading role" in the company, Judge Carroll said, jailing him for five years.
Qualified accountant Whitehead, from Bury St Edmunds in Suffolk, had acted as the company's finance director.
The 60-year-old, who the court heard was previously cautioned for fraud, was handed a three-and-a-half-year sentence.
King, TCL's office manager, from Basildon, Essex, broke down in tears as she was jailed for 27 months.
The court heard the mother-of-four had previously been given a suspended sentence for benefit fraud.
Muldoon, who was jailed in 2010 for fraud offences, fled the UK after being questioned about TCL's activities and was extradited from Spain last year.
Judge Carroll, handing the Basildon man a four-year sentence, said he had been an "unscrupulous salesman preying on people who wanted to make investments for their future".
Todd, of Tower Hamlets, east London, is currently serving time in prison for a similarly-styled "land banking" fraud. He was sentenced to one year behind bars, to run consecutively with his current term.
Docker, of Chigwell, Essex, is to be sentenced later on Friday.
Detective Inspector Matt Durkin from Surrey Police, who led the investigation, said: "This is a criminal gang who, dressed in suits, used big, long complicated words and flashy brochures but, fundamentally, they are just criminals."
