Republic Health is the target of an SEC probe.

Republic Health Corp. of Dallas, which in March became the largest privately held hospital management company after stockholders approved a $406.2-million leveraged buyout, is the subject of an insider trading investigation by the Securities and Exchange Commission. Republic said the investigation was launched March 5 “into trading in securities of Republic” from Jan. 1, 1985, through March 5, 1986, as well as “certain individuals, including some current and former officers, directors and employees of Republic.”