Goldman Worker Warned Roommate on Banker’s Insider Tips

Jean Wang, who works in fixed-income sales for Goldman Sachs Group Inc. in London, told her roommate in 2009 that buying shares based on tips from a Mizuho International Plc banker she was in a relationship with was insider trading.

Wang’s former roommate, Jessica Mang, a British chiropractor, is on trial accused of making 65,000 pounds ($104,000) trading on illegal tips about Canon Inc.’s acquisition of OCE NV in 2009 that she got from her then-boyfriend, former Mizuho banker Thomas Ammann.

“I basically said I don’t think Thomas should be doing that, that’s insider trading,” Wang testified at a London court today. “My impression was it was the deal he was working on and he was relatively sure it would happen.”

Mang is on trial with another of Ammann’s girlfriends, Christina Weckwerth. The U.K. Financial Services Authority, which is prosecuting the case, said Weckwerth took in nearly 2 million pounds from her trading on the same deal. Both paid half the profits they made to Ammann, a lawyer for the FSA said during the first day of trial last week.

Wang and Mang, who were high school classmates, lived together in central London from 2007 until April 2010. Wang said they were friends and she didn’t like Ammann because he didn’t treat Mang with enough respect, failing to show up for Mang’s birthday and once keeping her waiting for three hours at a Haagen Daz ice cream shop.

Canon Adviser

Ammann, who worked for the Mizuho mergers and acquisitions team that advised Canon on the OCE deal, pleaded guilty earlier this year to insider trading and encouraging both women to commit insider trading. Canon, the Tokyo-based maker of cameras and photocopiers, agreed to buy OCE in a 730 million-euro (953 million) deal in November 2009.

Wang said she was surprised to hear Ammann wanted Mang to make an investment and told her it was insider trading. Wang said she didn’t explain what insider trading was to her then-roommate and only mentioned it once -- a mention that was “probably not something she recognizes as significant.”

“It was more the suggestion that he should know better,” Wang said. “I didn’t go further into details with it with Jess.”

Mang bought OCE shares and then sold them five days later for almost twice what she invested, the FSA said. She wrote in her diary that Ammann advised her to invest.

The trial is scheduled to last as long as five weeks.

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