According to the ETF Finder at ETF Channel, MD makes up 2.70% of the SPDR S&PHealth Care Services ETF (XHS) which is lower by about 0.7% on the day Wednesday.
In afternoon trading Wednesday, MD was down about 0.2% on the day.
The physician-run company is more likely to buy than be bought.
The buyout firm owned TeamHealth years ago, eventually taking the physician staffing company public in 2009. It has agreed to be taken private for about $6.1 billion.