A company exploited foreign workers it had illegally supplied to about 500 farms across the country, a jury has been told.

Marden Management Ltd and its boss Christopher Blakeney, 50, are accused of having flouted gangmaster laws by providing workers, mainly Filipinos, to the dairy industry.

It is said they breached regulations introduced in the wake of the Morecambe Bay tragedy, when 21 cockle pickers died, by not having a licence. They deny the charges.

Brendan Moorhouse, prosecuting, told Swindon Crown Court the Wiltshire-based firm had applied for the permit in 2006 but were refused as the £2,130 required was not paid.

And, despite being warned that they were contravening the regulations when they asked if they were exempt, he said they kept on with the illicit trade.

Blakeney, of Conock, near Devizes, and Marden Management Ltd, of Calne, each deny four counts of acting as a gangmaster without the proper licence.

The jury was told workers were brought into the UK, having already provided financial bonds, and were then deducted half their first two months' wages as a second bond.

Some were then subject to deductions for accommodation, which was supposed to be provided by the farmer.

Time sheets were not properly kept, meaning they worked extra hours for nothing, and many were paid less than the Agricultural Minimum Wage.

"Every opportunity to take that extra little bit of money out of them was taken by the company as part of their exploitation," Mr Moorhouse told the jury.

He said the company had suggested to the Gangmaster Licensing Agency they did not need the permit as their workers fell into certain exempt categories.

"Marden Management were told that those exclusions did not apply to them at that stage and told why," he said.

One ruse was to try and get round the rules was to set up a 'bogus educational scheme' to claim the workers were trainees and so were exempt from the rules, he said.

The offending was said to have taken place between October 2006, when the law changed, and June 2010.

"During that time there was systematic underpayment of workers, money unlawfully withheld, money deducted, workers in poor conditions with no alternative but to carry on because of the bonds held against them," he said.

Blakeney and Marden Management deny any wrongdoing. The case continues.