Pfizer Inc. (NYSE:PFE) is popping today, following several of its fellow biotech stocks higher. At last check, PFE shares were up 3% to trade at $35.37, and earlier hit a 13-month high of $35.75. Bullish options traders are flooding the Dow stock, too, with one trader eyeing even higher highs over the next several months.

With around two hours left in the trading session, nearly 132,000 PFE calls have traded -- 12 times the expected intraday rate, and a new 52-week peak -- compared to 15,000 puts. Most notably, a block of 52,637 January 2018 36-strike calls changed hands for 72 cents apiece. Trade-Alert indicates the calls were bought to open, creating an initial cash outlay of roughly $3.8 million (number of contracts * premium paid * 100 shares per contract).

This is the most the call buyer stands to lose, should PFE settle below $36 at the close on Friday, Jan. 19. Profit, meanwhile, will accumulate on a move above breakeven at $36.72 (strike plus premium paid). Delta on the call is docked at 0.42, pointing to a 42% chance it will expire in the money.

This bullish bias isn't anything new for Pfizer options traders. At the International Securities Exchange (ISE), Chicago Board Options Exchange (CBOE), and NASDAQ OMX PHLX (PHLX), speculative players have bought to open 18,227 calls in the last 10 days, compared to 5,921 puts. The resultant call/put volume ratio of 3.08 ranks in the 78th annual percentile, meaning long calls have been initiated over puts at a faster-than-usual clip.

Echoing this call-skew is PFE's Schaeffer's put/call open interest ratio (SOIR) of 0.60, which rests lower than 93% of all comparable readings taken in the past year. In other words, traders have rarely been more call-heavy among options set to expire in three months or less.

It's a prime time to buy short-term options on Pfizer stock, too. Its Schaeffer's Volatility Index (SVI) of 11% ranks just 1 percentage point from a 52-week bottom, indicating extremely low volatility expectations are being priced into near-term options.

Health foods retailer United Natural Foods, Inc. (NASDAQ:UNFI) will report earnings tomorrow night. While earnings season has mostly wrapped up, UNFI's report will be of interest, considering Amazon's successful foot traffic with Whole Foods after its price cuts. Below, we will take a look at United Natural Foods' earnings history, and how investors are trading the equity.

At last check, UNFI stock is up 1.6% today to trade at $36.62. However, the health foods stock has had a tough 2017, dropping 23% amid a channel of lower highs and lows beneath its 80-day moving average. A negative earnings reaction in June sent the stock to a nearly seven-year low of $29.53, and United Natural stock's rebound attempt in late July/early August was thwarted by the $40 region -- where UNFI shares were trading before the bear gap.

UNFI stock has averaged a one-day move in either direction of 6.4% in the session following its last eight earnings releases, per Trade-Alert. However, the stock has reacted negatively following six of the last eight reports, and moved lower after its last four turns in the earnings spotlight. In anticipation of tomorrow, the options market is pricing in a bigger-than-usual one-day swing of 10.8%, per the stock's at-the-money implied volatility data. 

Wall Street sentiment skews tremendously bearish toward UNFI -- not too surprising, considering the security's performance of late. Of the 10 brokerages covering UNFI stock, nine rate it a "hold" or "strong sell." Further, Pivotal Research Group today predicted disappointing guidance from United Foods tomorrow, and reiterated a "sell" rating, stating, "The longer-term implications from Amazon [buying Whole Foods] can't be viewed in a favorable light." The analysts also warned that "UNFI may be on an unsustainable path based on the recent rounds of cost cutting."

There also remains a great amount of capital tied up in UNFI short interest. While short interest decreased by 4% during the last reporting period, the 7.4 million shares currently sold short represent a healthy 15% of the stock's total available float, or more than 23 times United Natural Foods' average daily trading volume.

September is historically been a weak month for the Health Care Select Sector SPDR Fund (XLV). According to data from Schaeffer's Quantitative Analyst Chris Prybal, the fund has averaged a 1.7% loss in September since its inception. Nevertheless, XLV is bucking this bearish trend so far this month -- thanks in part to a big surge for Pfizer -- up 2.4% since its Aug. 31 close to trade at $93.25, and earlier hitting a record high of $83.36. Options traders, meanwhile, think the shares could run even higher by year's end.

Nearly 28,000 calls have changed hands today -- eight times what's typically seen, and volume pacing in the 91st annual percentile. Most of the action has centered on the December series, where it looks like one trader may have sold to close December 83 calls and used the funds to initiate new long positions at the December 87 call. If this is the case, the trader thinks XLV will rally past $87 by the close on Friday, Dec. 15 -- when the options expire.

This accelerated call buying echoes a recent trend in XLV's options pits. At the International Securities Exchange (ISE), Chicago Board Options Exchange (CBOE), and NASDAQ OMX PHLX (PHLX), the fund's 10-day call/put volume ratio of 1.52 ranks in the 73rd annual percentile, meaning long calls have been initiated relative to puts at a quicker-than-usual clip. 

However, this call buying coincides with a recent uptick in XLV short interest. After hitting a seven-year low in mid-July, short interest rose 19.07% in the two most recent reporting periods to 21.70 million shares. As such, short sellers could be initiating options hedges to guard against any additional upside risk. 

Regardless of the reason, speculators are currently able to purchase premium on XLV options at relatively tame levels. The fund's Schaeffer's Volatility Index (SVI) 12% ranks in the 13th annual percentile, suggesting short-term options are pricing in comparatively low volatility expectations at the moment.

The big Apple Inc. (NASDAQ:AAPL) product unveil is finally upon us -- almost. The tech giant will host an event tomorrow where it's expected to release the newest iPhones. But while the stock is up 2.1% today at $161.89, it actually just wrapped up a four-day losing streak. Still, sentiment among AAPL options traders appears bullish heading into the iPhone release, with some expecting Apple stock to rally to fresh record highs in the coming weeks. 

Starting with data from the International Securities Exchange (ISE), Chicago Board Options Exchange (CBOE), and NASDAQ OMX PHLX (PHLX), the equity has a 10-day call/put volume ratio of 2.31 -- showing call buying has more than doubled put buying over the last two weeks. Plus, this reading outranks three-fourths of all others from the past year, showing this bullish bias is relatively rare. 

Looking at the top increases in open interest during the past 10 days, the October 170 call stands out, ranking third on the list. Data from the major options exchanges shows a near-even split of buy- and sell-to-open action at this strike. Those buying the calls expect Apple stock to climb above $170 by the close on Friday, Oct. 20, when the contracts expire, while the call writers are betting on this level serving as a short-term technical ceiling. 

Also seeing heavy interest during this time frame was the September 162.50 call, where most traders were buying to open positions. These contracts expire at the close on Friday, Sept. 15, so options traders are expecting AAPL to take out this price point by the end of this week.

In today's trading, calls are again active. In fact, Apple's single-day put/call volume ratio of 0.47 sits below 82% of similar readings from the past year. New positions are seemingly being opened at the September 160, 162.50, and 165 calls, as traders bet on a post-event rally from the shares. 

If you want to trade the event with options, you'll have to pay up. Specifically, the security's 30-day at-the-money implied volatility has jumped to 24.2%, which ranks in the 87th annual percentile, hinting at strong demand for near-term options. At the same time, AAPL has a Schaeffer's Volatility Scorecard (SVS) of 91, meaning it's shown a tendency to make bigger-than-expected moves on the charts over the past year, compared to what the options market has priced in. 

And while optimism builds among options traders, short sellers has continued to hit the exits. After falling another 3% in the latest reporting period, short interest on Apple is now the lowest it's been since at least 2002. 

It's hard to blame these bears for hitting the exits, since the stock is up 57% over the past 12 months, and hit a record high of $164.94 on Sept. 1. Plus, today's pop has AAPL back above the 20-day moving average, a trendline that's offered solid support since late July. 

Apple will host its highly anticipated iPhone event tomorrow, with rumors and leaks about the "iPhone X" already running rampant. Against this backdrop, several Apple suppliers are in focus today, and one stock could be screaming "buy," if history is any indicator: Texas Instruments Incorporated (NASDAQ:TXN). Below, we'll take a look at how TXN stock has performed on the charts, and why Texas Instruments' short-term options could be a relative bargain.

TXN shares have spent the past few months dawdling between support in the $80 region and resistance in the $83-$84 area. However, the stock recently came within one standard deviation of its 80-day moving average, after a lengthy time above this trendline. According to data from Schaeffer's Senior Quantitative Analyst Rocky White, after the last nine similar occurrences, Texas Instruments stock enjoyed a one-month rally 78% of the time, averaging a healthy gain of 3.86%. At last check, TXN shares were up 1.4% at $82.50; another 3.86% rally would put the stock around $85.68 -- in territory not explored since 2000.

Options traders looking to speculate on Texas Instruments stock's short-term trajectory can do so at a relative discount, too. The equity's Schaeffer's Volatility Index (SVI) is in the bottom third of its annual range, pointing to historically attractive near-term premiums right now.

While TXN options volume tends to run light, on an absolute basis, recent buyers have been upping the bullish ante. On the International Securities Exchange (ISE), Chicago Board Options Exchange (CBOE), and NASDAQ OMX PHLX (PHLX), the stock's 10-day call/put volume ratio of 1.40 is higher than 79% of all other readings from the past year, pointing to a healthier-than-usual appetite for long TXN calls over puts.

Shares of GoPro Inc (NASDAQ:GPRO) have been tearing up the charts since early August -- gapping higher last week on the tech name's strong guidance -- with today's price action just more of the same. At last check, GPRO stock was 8% higher at $11.08, after Citigroup raised its price target to $10.50 from $9.50. As the security takes aim at its highest close on 2017, options traders are piling on, with calls and puts crossing at two times what's typically seen at this point in the day.

By the numbers, 10,617 calls and 5,904 puts have traded so far, with front-month September strikes accounting for seven of GPRO's 10 most active options. In the lead is the September 11 call. It looks as if some of the activity could be of the buy-to-open kind, in which case speculators are betting on GoPro stock extending its recent rally through expiration at this Friday's close.

This penchant for long calls is nothing new for GoPro options traders, though. At the International Securities Exchange (ISE), Chicago Board Options Exchange (CBOE), and NASDAQ OMX PHLX (PHLX), the stock's 10-day call/put volume ratio of 2.14 ranks in the 68th annual percentile -- meaning calls have been bought to open over puts at a faster-than-usual clip.

However, there could be an ulterior motive to this accelerated call buying. Considering how heavily shorted GoPro is -- more than one-quarter of its float is dedicated to these bearish bets -- short sellers could be initiating options hedges against any additional upside risk. 

Whatever the reason, now is a prime time for traders to buy premium on short-term GoPro options. While its 30-day at-the-money implied volatility of 47.7% ranks in the 13th annual percentile, its Schaeffer's Volatility Index (SVI) of 46% ranks lower than 93% of all comparable readings taken in the past year. These two volatility indicators suggest relatively muted expectations for GPRO.

Coal stock Teck Resources Ltd (USA) (NYSE:TECK) has been hot since bottoming at $14.56 in mid-June, topping out at $25.67 back on Sept. 1. The shares have pulled back slightly since then, last seen trading at $23.52, but data suggests they could be due for a bounce. Schaeffer's Senior Quantitative Analyst Rocky White notes that TECK stock has pulled back to within one standard deviation of its 40-day moving average, a trendline that historically has had extremely bullish implications. 

Specifically, the security has pulled back to this moving average six times over the past three years, and each time it's been higher a month later. In fact, it's averaged a mind-bending gain of 25.6% after such occasions. And just below this key technical level is a 61.8% Fibonacci retracement of TECK's 2016 high to its 2017 low. 

Analysts are certainly remaining upbeat. Of the 14 brokerages covering Teck Resources, 11 have given out "strong buy" ratings. However, another strong bounce off its 40-day trendline could encourage the three remaining holdouts to upwardly revise their ratings.

Options traders seem bullish, too. TECK has a 10-day call/put volume ratio of 2.73 at the International Securities Exchange (ISE), Chicago Board Options Exchange (CBOE), and NASDAQ OMX PHLX (PHLX), meaning call buying has nearly tripled put buying over the past two weeks. However, volume has been light on an absolute basis. 

U.S. stocks are trading higher this afternoon, with the Dow up over 200 points and pacing to end above the 22,000 level for the first time in almost a month. Among the stocks swimming in the red today are medical technology company Pulse Biosciences Inc (NASDAQ:PLSE), insurance stock Health Insurance Innovations Inc (NASDAQ:HIIQ), and credit bureau Equifax Inc. (NYSE:EFX). Here's a quick look at what is moving shares of PLSE, HIIQ, and EFX.

Pulse Biosciences Stock Tanks After Company Pulls Marketing Application

Shares of Pulse Biosciences are down 15.7% to trade at $16.49, after the company withdrew its marketing application for its PulseTx medical device -- a nano-pulse stimulation platform -- due to a lack of required data. The medical technology company plans to resubmit an application for the device to the U.S. Food and Drug Administration (FDA) within the next few months.

Today's drop sent PLSE to an intraday low of $11.77 -- territory it hasn't visited since February -- and the shares were briefly halted in early trading. Ranking among the worst stocks on the Nasdaq today, PLSE is poised to close below its 200-day moving average for just the third time ever. The stock -- which was red-hot in the first half of 2017 -- has dropped 58% since touching a record high of $39.50 in June, but remains 153% higher year-to-date.

Plenty of shorts are likely cheering today's decline, as short interest represents roughly 22% of PLSE's total available float. At the equity's average daily trading volume, it would take more than seven sessions to cover the shorted shares. However, Pulse Biosciences stock is on the short-sale restricted (SSR) list today.

HIIQ Falls After Mox Reports Tweets Short Position

The worst stock on the Nasdaq today is Health Insurance Innovations, last seen down 28.4% at $21.35. HIIQ shares are down after activist Mox Reports tweeted that it's shorting the stock, citing potential fraud penalties of more than $100 million and an "undisclosed 'domino effect.'" In addition, Mox said HIIQ could drop below $1 and face delisting.

HIIQ shares hit a record high of $37.37 on Aug. 30, but have since dropped 47% to today's intraday low of $19.70. Now, HIIQ is trading near its 200-day moving average -- a trendline the stock hasn't touched since last November. HIIQ could be vulnerable to bearish brokerage notes, as five of the six analysts following the stock rate it a "strong buy," and not one rates it a "sell." 

Equifax Continues to Sink on Senator's Tweetstorm

Last seen down 8% at $113.43 -- and ranking among the worst on the New York Stock Exchange (NYSE) -- is Equifax stock. EFX shares on Friday gapped lower on news of a massive data breach that compromised personal information of 143 million U.S. customers, and a scathing tweetstorm from a U.S. Senator isn't helping matters today. Among the many tweets to Equifax today, Hawaii's Brian Schatz asked, "Why did senior executives liquidate their stock after finding out what happened?"

Now down 4.3% in 2017, EFX is pacing for its second straight close below its 200-day moving average since February. Short-term option players have rarely been more put-heavy, as evidenced by EFX's Schaeffer's put/call open interest ratio (SOIR) of 4.98, which stands just 4 percentage points from an annual high.

Shares of Tesla Inc (NASDAQ:TSLA) are getting a big boost today on reports China is planning to eventually ban gasoline vehicles and is on track to install 800,000 new charging stations for electric vehicles by the end of 2017. TSLA stock was last seen up 5.4% at $362.06, bringing its year-to-date gain to 69.4%. And with the equity breaking out above a trendline connecting lower highs since August, options traders are betting on even more upside by week's end.

With just about an hour left in today's trading, roughly 76,250 TSLA calls and 60,000 puts have changed hands -- 1.4 times the expected intraday rate. The front-month September series accounts for Tesla's 10 most active options, with the September 360 and 370 calls taking the top two spots. It seems safe to assume new positions are being purchased here, with options traders betting on the stock closing north of the strikes at this Friday's close, when the options expire.

Tesla options traders have been quick to initiate long calls relative to puts in recent weeks. At the International Securities Exchange (ISE), Chicago Board Options Exchange (CBOE), and NASDAQ OMX PHLX (PHLX), 77,360 calls have been bought to open in the past two weeks, compared to 63,245 puts. The resultant call/put volume ratio of 1.22 ranks higher than 80% of all comparable readings taken in the past year.

While it's likely that some of this activity is a result of "vanilla" call buyers, it's also possible short sellers are buying out-of-the-money calls to hedge their bearish bets against any upside risk. After spending 2017 declining from an early December record high, short interest has started to turn higher. Specifically, it rose 2.2% in the most recent reporting period to 28.70 million shares -- 24% of Tesla's available float.

Regardless of what call buyers' motive may be, it's an attractive time to purchase premium on the stock. Per TSLA's Schaeffer's Volatility Index (SVI) of 33% -- in the 19th annual percentile -- low volatility expectations are being priced in to short-term options. Plus, the security's Schaeffer's Volatility Scorecard (SVS) of 96 indicates the shares have tended to make bigger moves than what the options market has anticipated over the past year.

While Apple and its suppliers dominate headlines ahead of tomorrow's iPhone reveal, the shares of Netherlands-based chipmaker ASML Holding NV (ADR) (NASDAQ:ASML) have quietly hit record highs today. What's more, a weekend article from Barron's (subscription required) suggested ASML could be a lower-profile alternative to the more popular FAANG stocks. Below, we will break down ASML stock's performance, and see how its options stack up against the FAANG crowd.

Not Everyone Is Buying Into ASML's Rally

At last check, ASML Holding stock was up 1.8% to trade at $162.64, and earlier touched a new all-time high of $162.88. It's been a stellar run for the chip stock, which has tacked on 60% year-over-year, and has been stair-stepping higher since early 2016. Even before today, the stock had outperformed the broader S&P 500 Index (SPX) by 17 percentage points during the past three months.

While short interest decreased during the last reporting period, the 3.08 million shares sold short represent over a week's worth of potential buying power, at ASML's average daily trading volume. A short squeeze could send the stock to new heights.

Despite the stock's strong run lately, analyst sentiment also remains subdued. Over two-thirds of the analysts covering ASML rate the stock a tepid "hold." This indicates that there is plenty of room for upgrades, which could provide more tailwinds for the stock.

ASML Options Traders Pick Up Calls

In the options pits, while absolute volume runs relatively light, there has been an overwhelming preference for calls. ASML stock's Schaeffer's put/call open interest ratio (SOIR) of 0.72 is 2 percentage points from a 52-week low. This suggests that near-term option traders have rarely been more call-biased in the past year. Digging deeper, the in-the-money September and October 155 calls are home to peak open interest, with over 1,700 contracts outstanding apiece.

The preference toward calls is echoed by data from the International Securities Exchange (ISE), Chicago Board Options Exchange (CBOE), and NASDAQ OMX PHLX (PHLX), which shows ASML with a 50-day call/put volume ratio of 5.77 that ranks in the 84th percentile of its annual range.

The good news for these buyers is that ASML's near-term options are attractively priced, relatively speaking. ASML's Schaeffer's Volatility Index (SVI) of 23% is higher than just 21% of all other readings from the past year, implying that short-term options are pricing in relatively low volatility expectations. However, it's worth noting that FAANG members Amazon, Facebook, and Netflix stock boast even lower SVIs, and the latter could also be ripe for a short squeeze.

The Dow is poised to make a triple-digit jump this morning. Among specific stocks in focus are drug stocks Teva Pharmaceutical Industries Ltd (ADR) (NYSE:TEVA), Marinus Pharmaceuticals Inc (NASDAQ:MRNS), and Achillion Pharmaceuticals, Inc. (NASDAQ:ACHN). Here's a quick look at what's boosting shares of TEVA, MRNS, and ACHN. 

TEVA Stock Eyes Major Upside After CEO Announcement

Teva Pharmaceutical stock has been battered for months, falling to a 15-year low of $15.22 last week, before closing Friday at $15.50. The shares are set for a major comeback this morning, however, after the company announced Kaare Schultz as its new CEO. In response, TEVA is ready to open 14% higher.  

If these gains come to fruition, it could be a big day for options traders, as well. For instance, Teva Pharmaceutical has a 10-day call/put volume ratio of 3.04 at the International Securities Exchange (ISE), Chicago Board Options Exchange (CBOE), and NASDAQ OMX PHLX (PHLX). Not only does this show call buying has tripled put buying during the past two weeks, but this reading ranks in the 90th annual percentile. 

Marinus Pharmaceuticals is also ready to surge today, thanks to news of upbeat trail results for the company's epilepsy treatment, ganaxolone. This penny stock has been delivering monster gains, rising from a Dec. 30 close of $1.01 to settle Friday at $3.12. And with today's news, the shares are pointed another 51.9% higher. Meanwhile, a number of short sellers threw in the towel at the right time. Short interest on MRNS fell by 30.4% during the last two reporting periods. 

On the other end of the spectrum is Achillion Pharmaceuticals, down 23.6% in pre-market trading. This potential sell-off has been sparked by news Johnson & Johnson subsidiary Janssen Pharmaceutical has ended the two companies' collaboration on a hepatitis C treatment. ACHN stock closed last week at $4.91, well below its perch from this time last year when it traded near $8. 

Achillion is now in danger of negative attention from the brokerage bunch. Specifically, five of the seven analysts tracking the equity say it's a "strong buy," and its average 12-month price target stands at $7.14. Don't be surprised if downgrades and/or price-target reductions could through and pressure the shares further. 

Analysts are weighing in on online restaurant delivery service GrubHub Inc (NYSE:GRUB), cancer treatment specialist Array Biopharma Inc (NASDAQ:ARRY), and mining stock Tahoe Resources Inc (NYSE:TAHO). Here's a quick roundup of today's bullish brokerage notes on shares of GRUB, ARRY, and TAHO.

GRUB Stock Gets Mixed Messages from Credit Suisse

GrubHub stock has been flying up the charts since hitting an annual low of $32.43 in early April, up 73% and fresh off last Thursday's record high of $57.61. Nevertheless, Credit Suisse downgraded the shares to "neutral" from "outperform," although the brokerage firm did raise its price target to $53 from $50.

However, this still represents a discount to Friday's close at $56.08 -- and resides in the same ballpark as the stock's average 12-month price target of $52.89. Although GRUB shares are down 1.5% in electronic trading, they could garner more upwardly revised analyst ratings once they resume their longer-term uptrend.

ARRY Stock Gaps After Fresh Round of Price-Target Hikes

Array Biopharma stock is up 8.2% ahead of the bell, after Cantor, Cowen, and Stifel all raised their respective price targets on the stock to $15 -- representing expected upside of nearly 37% to last week's close at $10.98, and territory not seen since early 2002. The shares are up nearly 25% already this year, but have struggled to break out above the $12 mark, including during last Friday's bull gap in the wake of strong late-stage trial results for its colorectal cancer treatment.

A round of short covering could potentially help the stock topple this pesky technical ceiling. Nearly 16% of ARRY's float is sold short, representing 7.2 times the security's average daily pace of trading.

Credit Suisse Raised Its Rating on TAHO Stock

Tahoe Resources stock is set to jump 35.7% out of the gate, after the Guatemalan Supreme Court reinstated a license to the company's subsidiary, Minera San Rafael, for the Escobal mine -- the world's third-largest silver mine. Adding to the bullish bias is an upgrade to "outperform" from "neutral" from Credit Suisse. TAHO shares gapped lower when the license was initially suspended in early July, and hit a record low of $4.24 on Aug. 29. Longer term, TAHO is down 50% year-to-date, closing Friday at $4.70.

Short sellers have been cashing in their winning bets during this decline, too. Since hitting a record high of 10.28 million shares sold short in early May, short interest on the security is down almost 27%.