Most Active Options Update: Amazon.com, Inc. and Tesla Motors Inc

The 20 stocks listed in the table below have attracted the highest total options volume during the past 10 trading days. Names highlighted are new to the list since the last time the study was run, and data is courtesy of Schaeffer's Senior Quantitative Analyst Rocky White. Two names of notable interest are e-commerce concern Amazon.com, Inc. (NASDAQ:AMZN) and electric vehicle maker Tesla Motors Inc (NASDAQ:TSLA).

AMZN is up 1.6% at $553.29, as traders celebrate lackluster subscriber statistics for programming rival Netflix, Inc. (NASDAQ:NFLX). Looking ahead, AMZN is slated to take its turn in the earnings confessional one week from today, the night of Thursday, Oct. 22.

During the past two weeks, AMZN options traders have purchased puts over calls at a faster-than-usual clip, suggesting speculators are either betting on or hedging against a pullback. On the International Securities Exchange (ISE), Chicago Board Options Exchange (CBOE), and NASDAQ OMX PHLX (PHLX), the equity's 10-day put/call volume ratio of 1.13 stands higher than 92% of all other readings from the past year.

Echoing that, AMZN's Schaeffer's put/call open interest ratio (SOIR) sits at 1.38 -- in the 89th percentile of its annual range. In other words, short-term option players have rarely been more put-biased during the past year.

What's more, near-term traders are paying a relatively pretty premium to gamble on Amazon.com, Inc. (NASDAQ:AMZN), which has added 8% in October and a whopping 78% year-to-date. With volatility expectations rising into earnings, the stock's Schaeffer's Volatility Index (SVI) is docked at 45% -- higher than 81% of all other readings from the past year. 

Meanwhile, TSLA is up 0.9% at $218.69, as speculators digest the company's "autopilot" software update. The stock has shed 12% so far in October, and is now testing its mettle in the $215-$220 neighborhood, which contained its pullback in late August, and is home to the security's ascending 100-week trendline.

During the past 50 sessions at the ISE, CBOE, and PHLX, the stock has racked up a put/call volume ratio of 1.00 -- higher than 72% of all other readings from the past 12 months. Or, simply put, TSLA traders are buying to open puts over calls at an accelerated clip, relatively speaking.

Over the last two weeks, the October 210 put has garnered buy-to-open action, and open interest at this strike increased by nearly 6,200 contracts -- the most of any strike. The puts will move into the money if TSLA breaches $210 -- territory charted just once (on Aug. 24) since mid-April -- by the close on Friday, when front-month options expire.

Likewise, short interest accounts for nearly 26% of Tesla Motors Inc's (NASDAQ:TSLA) total available float, and would take more than six sessions to buy back, at the security's average pace of trading. Should TSLA shares rebound off familiar support, a mass exodus of option bears or a short squeeze could add fuel to the stock's fire.