The Wall Street Journal also reported Wednesday that the Securities and Exchange Commission opened an inquiry into Herbalife. The Journal cited an unidentified person familiar with the matter. Representatives for the SEC and Herbalife both declined to comment.
Herbalife's stock hit a low of $24.24 in late December as a result of Ackman's allegations, their lowest point since July 2010. Shares have lost close to half their value since the end of April.
The company's stock fell $1.84, or 4.4 percent, to $38.11 in afternoon trading Thursday.
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