The Wall Street Journal reported the two federal authorities are investigating whether Mickelson and Las Vegas bettor William "Billy" Walters traded illicitly on Icahn's private information about his investments in public companies. The investigators are looking into whether Icahn tipped off Walters during the past three years about his investments that could have moved the market.
The investigators are also checking into whether Walters tipped off Mickelson at least once and are studying the two men's trading patterns.
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Icahn has denied the claims. "We do not know of any investigation," he said Friday. "We are always very careful to observe all legal requirements in all of our activities." He called the reports of insider trading "inflammatory and speculative." Icahn also said he has heard of Mickelson but has never "spoken to him or met him."
Mickelson said in a statement Saturday he has done nothing wrong and would cooperate with the investigation.
The stock was down 2.94% to $99.39 at 10:34 a.m.
Separately, TheStreet Ratings team rates ICAHN ENTERPRISES LP as a "hold" with a ratings score of C. TheStreet Ratings Team has this to say about their recommendation:
"We rate ICAHN ENTERPRISES LP (IEP) a HOLD. The primary factors that have impacted our rating are mixed - some indicating strength, some showing weaknesses, with little evidence to justify the expectation of either a positive or negative performance for this stock relative to most other stocks. Among the primary strengths of the company is its solid stock price performance. At the same time, however, we also find weaknesses including unimpressive growth in net income, generally higher debt management risk and disappointing return on equity."