Analyst Update: Twitter, Google, and Infinera

Analysts chimed in on social media firm Twitter Inc (NYSE:TWTR), Internet search behemoth Google Inc (NASDAQ:GOOGL), and network gear provider Infinera Corp. (NASDAQ:INFN). Here's a quick roundup of today's brokerage notes on TWTR, GOOGL, and INFN.

• TWTR is 2.2% lower at $27.55, after Moffett Nathanson started the stock with a "neutral" rating and $30 price target. The coverage on Twitter Inc was part of a larger move by the brokerage, which initiated the Internet sector with an "overweight" rating, and weighed in on stocks like Facebook Inc (NASDAQ:FB) and Walt Disney Co (NYSE:DIS). In addition, Mike Gupta, a senior vice president at Twitter Inc, was lured away by startup company Docker. Technically, today's drop is a continuation of the social media giant's overall trend. The stock hit an all-time low of $21.01 last month and has rebounded slightly, but continues to stare up at potential resistance in the round-number $30 region -- home to TWTR's 10-week moving average. Meanwhile, option players have upped the bearish ante. TWTR's 50-day put/call volume ratio on the International Securities Exchange (ISE), Chicago Board Options Exchange (CBOE), and NASDAQ OMX PHLX (PHLX) checks in at 0.43, in the 83rd percentile of its annual range. Additionally, the firm has drawn the ire of analysts recently, and continued poor performance could draw more attention, as half the brokerage firms following TWTR maintain a "strong buy."

• GOOGL is 1.7% higher at $639.48 this afternoon, after Moffett Nathanson started the search giant at "buy" with a $730 price target -- in uncharted territory. Since gapping higher in mid-July, Google Inc shares have found support at their 50-day moving average. Meanwhile, option players have stocked up on long puts -- though at a relative discount. GOOGL's 10-day ISE/CBOE/PHLX put/call volume ratio of 0.82 ranks in the 96th percentile of its annual range. 

• INFN is 3.7% lower at $20.61, due to a downgrade from Goldman Sachs. The brokerage cut Infinera Corp. to "sell" and slashed its price target to $19 from $24. The ratings house sees "downside risks to Street estimates as the company moves from a single-product portfolio to a full solution set ... [Which] will cause gross margin headwinds over the next year." While INFN has nearly doubled over the past year, and hit a seven-year high of $25.24 in mid-August, option players are skeptical, as INFN's 50-day ISE/CBOE/PHLX put/call volume ratio of 0.66 is higher than 93% of the readings taken in the past 52 weeks.