Ex-Banker’s Girlfriend Says Trades on Tips Showed Trust

British Chiropractor Jessica Mang
Jessica Mang, a 30-year-old British chiropractor, was cleared today by the jury after a four-week trial. Photograph: Rex Features via AP Images

Jessica Mang, one of the ex-girlfriends of former Mizuho International Plc investment banker Thomas Ammann, said she bought shares at his request because she wanted to show that she trusted him.

Mang invested her own money because Ammann demanded it and said they could go on a vacation together afterward, she testified today at a London criminal court. Mang is on trial for insider trading along with Christina Weckwerth, another woman with whom Ammann simultaneously had a relationship.

“He basically said that I show him that I trust him -- I invest the money, he still hadn’t specified how -- once that’s done, we’ll go on holiday in the Seychelles,” Mang said. If she didn’t do it, Ammann said “he didn’t want to be with me anymore,” she said, adding that he told her the investment would bring a 70 percent to 80 percent return.

Mang, 30, a British chiropractor, is accused of getting 65,000 pounds ($103,700) from an investment of about 39,000 pounds trading on tips about Canon Inc.’s acquisition of OCE NV in 2009 that she got from Ammann, who was advising on the buyout. The U.K. Financial Services Authority, which is prosecuting the case, said Weckwerth took in nearly 2 million pounds from her trading on the improper tips.

Both women paid half the profits to Ammann, a lawyer for the FSA said at a prior hearing.

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 ($933.8 million) deal in November 2009.

Due Diligence

Mang, who was born in Hong Kong, met Ammann at a nightclub in London in July 2009. Initially they saw each other at least once a week. He never mentioned Weckwerth, she said.

The first time investing came up was during a conversation in which Mang was asking about their future together, she said.

“Somehow it got to him asking me about whether I had savings, what I did with it,” Mang said. “He said we’re trying to get to know each other better” and called it due diligence.

Mang said she didn’t know what due diligence was and “thought it was just a cute nickname he had for me.”

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


“I thought, you know, this is a relationship that’s going to go somewhere, I definitely thought we were exclusive as well,” Mang said. “It wasn’t just sleeping together, in my mind we were definitely boyfriend-girlfriend from the start.”

Ammann suggested that she should invest so they could build a future together, which she said she thought was a “very sweet and considerate thing he was doing.”

The Seychelles holiday idea “was a massive leap in commitment,” she said she thought at the time.

Weckwerth, 44, testified earlier in the trial that she didn’t know Ammann’s work was related to the tips and she did her own analysis before deciding to buy the stock. She said she bought shares after she researched OCE on his recommendation.

Her calculations showed the shares, which were trading at about 2.50 euros in early 2009, were worth about 7 euros based on their net asset value, she said.

Mang said today she didn’t know what insider trading was, or that OCE was a takeover target and Ammann was working on the deal. She said that she struggled to set up an account to buy shares, and once she did, Ammann “more or less left it to my own device.”


She logged on to the account every morning to see how the shares were doing, and on Nov. 16, 2009, having seen that “it’s gone up a lot,” she sold it all.

“I’d done my trust-proving exercise,” Mang said. “I didn’t want to gamble anymore.”

She said she stayed with him after she was arrested by the FSA in November 2010. They broke up in April 2011, she said.

“He told me this is all a huge misunderstanding regarding his work and he can sort it out and I need to stay with him and support him” and to pay his legal bills, she said. She previously paid his rent twice, when he told her he couldn’t give his landlord a check because he was out of town. He never paid her back, she said.

Mang’s former roommate and close friend, Jean Wang, testified earlier in the trial that she warned Mang that what Ammann was doing was insider trading.

Mang said she doesn’t remember Wang, who works in fixed-income sales for Goldman Sachs Group Inc. in London, mentioning it, but that she wrote it in her diary at the time.

“I knew she worked in finance and who she worked for,” Mang said. “She would tell me funny anecdotal stories about her colleagues, about how when they had a mouse in the trading floor and they named it Ratatouille.”

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