Ninety-five year-old billionaire investor and mogul Kirk Kerkorian let his continued interest in the struggling casino MGM Resorts (NYSE:MGM) be known in a filing with the SEC yesterday. Kerkorian, whose net worth Forbes puts at $3.3 billion. already owns 18.6% of MGM's stock through Tracinda Corporation, a private investment company in which he is the sole shareholder.

Wednesday's 13D/A filing discloses Tracinda's intentions to increase its stake in the casino to up to 25%, though whether it will end up with that much of the company depends on "market conditions." Per MGM's trading policy, Kerkorian isn't even allowed to buy additional shares until the third trading day after MGM's next quarterly earnings release. With earnings not slated to be announced until Friday, May 3,, Kerkorian won't be able to add to his 91 million share, $1.2 billion stake in the company until at least Wednesday, May 8, when market conditions could have dramatically changed from where they stand today.

MGM shares were up as much as 7% on the news. 

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