Market Movers Today: Facebook, Inc. (FB), Geron Corporation (GERN), Heron Therapeutics Inc (HRTX), Micro Focus International PLC – ADR (MFGP), and More

Klondex Mines Ltd (NYSEAMERICAN:KLDX) (The Motley Fool)
What happened: Shares of Klondex Mines Ltd (NYSEMKT:KLDX) skyrocketed on Monday, up nearly 58% as of 10:45 a.m. EDT. Driving the surge was the announcement of a transaction with fellow gold miner Hecla Mining (NYSE:HL), whose stock tumbled more than 10% on the news. So what: Klondex Mines announced that it has agreed to be acquired by Hecla Mining for $462 million in cash and shares, representing a 59% premium to its trading price over the past 30 days.

Arista Networks Inc (NYSE:ANET) (MarketWatch)
Shares of Arista Networks Inc. ANET, -5.99% are down 4.4% in Monday morning trading after Deutsche Bank analyst Vijay Bhagavath downgraded the stock to sell from hold. Bhagavath also lowered his price target to $195 from $245. He points to “volatility in product orders” as well as his expectations that 100G switching orders will be weaker than anticipated. He also worries about the competitive landscape, writing that “a resurgent Cisco [Systems Inc. CSCO, -2.07% ] has been proactive in securing 100G Switch Router design wins at major cloud providers, and at enterprise multi clouds.”

Xerium Technologies, Inc. (NYSE:XRM) (Benzinga)
Xerium Technologies, Inc. shares surged 24.5 percent to $6.81 as the company reported a review of strategic alternatives to maximize shareholder value.

Qualcomm – Former chairman Paul Jacobs won’t be renominated to the chipmaker’s board, following news that he explored an effort to put together a potential buyout of the company his father founded. Reports say the board felt Jacobs could not be a director and work on a bid at the same time.

Cidara Therapeutics Inc (NASDAQ:CDTX) (Benzinga)
Cidara Therapeutics, Inc. fell 19.7 percent to $6.345. Cidara Therapeutics disclosed ‘positive’ topline results from Phase 2 STRIVE trial of lead antifungal rezafungin.