Ameristar Casinos shares decline despite upgrade

Shares traded as high as $14.60 Monday, an increase of nearly 9 percent over Thursday's closing price. The stock closed unchanged at $13.44. Shares have traded between $12.76 and $38 during the past 52 weeks.

JPMorgan analyst Joseph Greff raised Ameristar's stock to "Neutral" from "Underweight," noting that the company's stock had dropped roughly 25 percent since early June.

Also, Greff said the termination last week of Penn National Gaming Inc.'s $5.82 billion takeover deal by private investors is likely to increase speculation that Ameristar is now a target for Penn.

Penn received $225 million in cash as a termination fee, plus $1.25 billion in what amounts to no-cost capital until 2015.