Select Medical Holdings, a leading operator of specialty hospitals and outpatient rehabilitation clinics, announced terms for its IPO on Wednesday. The Mechanicsburg, PA-based company plans to raise $400 million by offering 33.3 million shares at a price range of $11.00 to $13.00. At the mid-point of the proposed range, Select Medical will command a market value of $1.8 billion. Select Medical, which was founded in 1996 and booked $2.2 billion in sales over the last 12 months, plans to list on the NYSE under the symbol SEM. Goldman Sachs, Morgan Stanley and BofA Merrill Lynch are the lead underwriters on the deal, which is expected to price during the week of Sept. 21.