An 11% drop in Black Friday sales sent the markets down to a lower open with the Dow tumbling 79 points to 17,748. Nasdaq dropped 38 points to 4,752.

On the upside

21Vianet Group (Nasdaq: VNET) announced an investment of $172 million from Kingsoft, $50 million from Xiaomi and $74 million from Temasek.

Bank of America analyst Paul Bieber upgraded Groupon (Nasdaq: GRPN) from a Neutral rating to a Buy rating and lifted his price target from $8 to $9.50.

Rising gold prices lifted shares of Barrick Gold (NYSE: ABX) and Kinross Gold (NYSE: KGC).

On the downside

U.S. retailers targeted Alibaba (NYSE: BABA) in a new ad saying that the Chinese ecommerce company would hurt local businesses by exploiting a sales tax loophole.

Exelixis (Nasdaq: EXEL) reported disappointing results from a Phase 3 trial of cabozantinib in men with metastatic castration-resistant prostate cancer.

Schools bought more Google (Nasdaq: GOOG) Chromebooks in the third quarter than Apple (Nasdaq: AAPL) iPads.

In the broad market, declining issues outpaced advancers by a margin of nearly 3 to 1 on the NYSE and by more than 5 to 2 on Nasdaq. The broader S&P 500 fell 12 points to 2054. Bitcoin added $1 to $378.