A man from Port Talbot has been sentenced to three years and nine months for fraudulently claiming almost £5m pounds worth of European Union and Welsh Government grants.
72-year-old Anthony Smith admitted claiming large sums of money to develop fish food.
The former steel worker made false promises that it would bring 120 jobs to Port Talbot and Pendine in Carmarthenshire. But only seven positions were created.
Smith was previously praised by Prince Charles and his products were used to feed trout served at restaurants run by Gordon Ramsay and Heston Blumenthal.
His ragworm product won awards and in 2008 he was invited to a private lunch at Windsor Castle with the Queen who told him the trout he had fed was "absolutely delicious".
But Smith was found to have gone on holidays to Bali and Hawaii and drove a Porsche and Lamborghini after being given the grants.
In 2006, he claimed £1m from the Welsh Government to build 270 ponds but fewer than a quarter of the ponds were installed.
A forensic accountant was previously hired to review financial accounts which revealed that Smith had structured his businesses, Dragon Research Ltd, Dragon Feeds Ltd and Dragon Baits Ltd, in order to hide the flow of illegitimate funds.
He ran the businesses with Colin Mair, 68, who admitted one count of fraudulent trading, and Keith Peters, 72, who admitted two counts of false accounting.
Colin Mair, 68, was sentenced to 21 months custody, suspended for 18 months and ordered to pay £15,000.
Chartered accountant Kevin Peters, 72, was jailed for one year and three months.
The Welsh Government said it "welcomed" the sentencing, and added it takes fraud "extremely seriously".
Whilst South Wales Police said the sentencing was the result of nearly a decade long investigation.
Smith pleaded guilty to three counts of fraudulent trading.