Watch These 10 Stocks Over The Weekend

Celyad SA CYAD gained about 10 percent in late trading Friday to $60.10. The Belgium-based drug company launched its initial public offering at $68.56 and closed down more than 15 percent earlier Friday.

Greenhill & Co., Inc. GHL gained more than 5 percent in Friday's extended session, trading at $42.23. The financial and advisory services company didn't issue news.

Braskem SA BAK rose about 3 percent in late trading to $8.27. The Brazilian thermoplastic resins producer closed down earlier by more than 11 percent. Its CEO was reportedly was arrested in a graft investigation on Friday.

Ctrip.com International, Ltd. CTRP bounced up nearly 3 percent after the bell Friday to $73.70 after closing down by nearly 4.5 percent. The China-based travel service provider priced a $1.1 billion offering of convertible notes Thursday.

Silver Bay Realty Trust Corp SBY rose about 2.5 percent to $16.10 in late trading Friday on no obvious catalyst.

InvenSense Inc INVN fell 3.4 percent to $15.50. The company, which provides gyroscopes, accelerometers, compasses and pressure sensors, didn't issue news.

Dorchester Minerals LP DMLP dipped 2.8 percent to $22.90. The Dallas-based mineral interests company didn't issue news Friday.

TransMontaigne Partners L.P. TLP declined 2.3 percent to $38 in late trading, although the terminal and transportation company for liquids didn't issue news.

Exelixis, Inc. EXEL dropped 2 percent after the bell to $3.76. The biopharma company had closed up about 7.6 percent earlier on no obvious catalyst.

Reynolds American, Inc. RAI fell nearly 2 percent to $75.53. As of Friday's closing, the tobacco company was up 7 percent during the past five trading days.