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• Seizure won't delay Mega listing - CEO
• Cops raid high roller
"The family trust has sold to eight different shareholders. Bill was one of them."
He said he had met Mr Yan on a number of occasions.
"We screened the guy before he invested. To me, he looked like a normal businessman."
Dotcom said he separated from management in Mega nine months ago to focus on the Internet Party, which has since merged with the Mana Party for this election.
He said he had not seen a press release issued which declared the shareholding had been seized but called it the "prudent" approach. "I don't know if it will have any negative effect. We're not happy about it."
Asked if it would impact on the Internet-Mana alliance, he said: "I don't think so."
Mega chief executive Graham Gaylard confirmed that 18.8% of the company was now under the control of the Official Assignee.
The police investigation into money laundering came after a drugs inquiry which saw 600kg of pseudoephedrine seized, a primary ingredient in methamphetamine.
Inquiries by the Herald have discovered the Metropolis raid stems from an ongoing financial investigation into a friend of Mr Yan, Yingzi Zeng, from whom $9 million in assets were seized in December.
Her assets, frozen by a High Court judge, included a late-model Porsche and Maserati, a $3.9 million lifestyle block, an apartment, a large home, bank accounts and businesses.
The court order was made alongside six others affecting people who face charges of importing and supplying the class-B drug pseudoephedrine following the record-breaking Operation Ghost investigation.
Hundreds of charges have been laid against more than 38 people in an inquiry where nearly 600kg of drugs have been seized. No charges have been laid against Ms Zeng, who lives in East Auckland, or Mr Yan.
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