Fears of a Greek default sent the markets down to a sharply lower open with the Dow plunging 127 points to 17,819. Nasdaq tumbled 41 points to 5,039.
On the upside
Sterne Agee upgraded Chesapeake Energy (NYSE: CHK) from an Underperform rating to a Buy rating and lifted its price target from $9 to $13.
Shares of Petrobras (NYSE: PBR) extended its gains.
On the downside
Shares of National Bank of Greece (NYSE: NBG) fell as Greek banks remained closed on Monday and a 60 euros daily limit on ATM cash withdrawals was implemented.
Profit taking weighed down shares of Seres Therapeutics (Nasdaq: MCRB).
Investors locked in profits on Penn Virginia (NYSE: PVA).
In the broad market, declining issues outpaced advancers by a margin of nearly 7 to 2 on both the NYSE and on Nasdaq. The broader S&P 500 dropped 13 points to 2087. Bitcoin rose $6 to $253.