The former Coca-Cola employee at the centre of a conspiracy trial was angry with her employer and was behind the plan to steal and then sell on company secrets, a co-defendant has told a US court.

Edmund Duhaney was charged in July with fraud and stealing and selling trade secrets along with Ibrahim Dimson and Joya Williams, a former executive administrative assistant at Coke.

Duhaney told the court yesterday (22 January) that Williams said her information could be worth a lot of money to Coke's rivals.

"She made a statement that Pepsi, the rival company, would be interested in this," Duhaney said, according to the Associated Press today.

Duhaney said he met with Williams and Dimson last April, a meeting at which Williams said she had information on Coke secrets, including data on Coca-Cola Blak.

"She felt she wasn't being treated right at her job," Duhaney said, according to AP.

He added that Williams told him she had been planning the scheme for some time, copying confidential documents little by little.

Williams' lawyer, Janice Singer, argued her client was duped by Duhaney and Dimson who had stolen documents from her and conspired behind her back, AP said.

In the report, Singer was quoted as calling Dimson and Duhaney as "two seasoned liars, con men who took advantage of Joya Williams."

Prosecutors allege that the trio tried to sell the information in deals worth US$1.5m. Coke learned of the theft and the attempted sale of the "very detailed and confidential information" from Pepsi, which was approached in May by an individual claiming to be a high-level Coke employee.

Pepsi received a letter from the individual, who called himself "Dirk" - alleged by prosecutors to be Dimson - and passed it on to Coke, which immediately contacted the FBI.