In April, the SEC ruled that companies may use social media such as Facebook and Twitter to make announcements.
A day before his first tweet about Apple, Icahn's website noted that he would use his Twitter account. "It is possible that the information that Mr. Icahn posts on Twitter (which may include information regarding companies in which we and/or Mr. Icahn have or may be contemplating an investment position) could be deemed to be material information," the site stated.
Icahn's dinner date with Cook hasn't come cheap — estimates have pegged his stake at between $1 billion and $1.5 billion — but then neither is Cook's time.
In May, an anonymous bidder plunked down $610,000 at an online auction to win a 30- to 60-minute meeting with Cook over coffee. Cook's offer was part a celebrity auction on CharityBuzz to raise money for the RFK Center for Justice and Human Rights, an international human rights organization based in Washington, D.C.
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