Should you sell Intuitive Surgical (Nasdaq: ISRG) today?

The decision to sell a stock you've researched and followed for months or years is never easy. If you fall in love with your stock holdings, you risk becoming vulnerable to confirmation bias -- listening only to information that supports your theories, and rejecting any contradictions.

In 2004, longtime Fool Bill Mann called confirmation bias one of the most dangerous components of investing. This warning has helped my own personal investing throughout the Great Recession. Now, I want to help you identify potential sell signs on popular stocks within our 4-million-strong Fool.com community.

Today I'm laser-focused on Intuitive Surgical, ready to evaluate its price, valuation, margins, and liquidity. Let's get started!

Don't sell on price
Over the past 12 months, the maker of the da Vinci Surgical System has risen 12.4% versus an S&P 500 return of 11.3%. Investors in Intuitive Surgical have every reason to be proud of their returns, but is it time to take some off the top? Not necessarily. Short-term outperformance alone is not a sell sign. The market may be just beginning to realize the true, intrinsic value of Intuitive Surgical. For historical context, let's compare Intuitive Surgical's recent price to its 52-week and five-year highs. I've also included a few other businesses in the same or related industries:

Company

Recent Price

52-Week High

5-Year High

Intuitive Surgical $283.74 $393.92 $393.90
Stryker (NYSE: SYK) $50.05 $59.72 $76.90
Zimmer Holdings (NYSE: ZMH) $52.33 $64.77 $94.40
Edwards Lifesciences (NYSE: EW) $67.05 $69.29 $105.90

Source: Capital IQ, a division of Standard & Poor's.

As you can see, Intuitive Surgical is down substantially from its 52-week high. If you bought near the peak, now's the time to think back to why you bought it in the first place. If your reasons still hold true, you shouldn't sell based on this information alone.

Potential sell signs
First up, we'll get a rough idea of Intuitive Surgical's valuation. I'm comparing Intuitive Surgical's recent P/E ratio of 36.3 to where it's been over the past five years.


Source: Capital IQ, a division of Standard & Poor's.

Intuitive Surgical's P/E is lower than its five-year average, which could indicate the stock is undervalued. A low P/E isn't always a good sign, since the market may be lowering its valuation of the company because of less attractive growth prospects. It does indicate that, on a purely historical basis, Intuitive Surgical looks cheap.

Now, let's look at the gross margins trend, which represents the amount of profit a company makes for each $1 in sales, after deducting all costs directly related to that sale. A deteriorating gross margin over time can indicate that competition has forced the company to lower prices, that it can't control costs, or that its whole industry's facing tough times. Here is Intuitive Surgical's gross margin over the past five years:



Source: Capital IQ, a division of Standard & Poor's.

Intuitive Surgical is having no trouble growing and maintaining its gross margin, which tends to dictate a company's overall profitability. This is solid news; however, Intuitive Surgical investors need to keep an eye on this over the coming quarters. If margins begin to dip, you'll want to know why.

Next, let's explore what other investors think about Intuitive Surgical. We love the contrarian view here at Fool.com, but we don't mind cheating off of our neighbors every once in a while. For this, we'll examine two metrics: Motley Fool CAPS ratings and short interest. The former tells us how Fool.com's 170,000-strong community of individual analysts rate the stock. The latter shows what proportion of investors are betting that the stock will fall. I'm including other peer companies once again for context.

Company

CAPS Rating

Short Interest (% of Float)

Intuitive Surgical 4 7.3%
Stryker 5 4.7%
Zimmer Holdings 4 4.3%
Edwards Lifesciences 2 3.8%

Source: Capital IQ, a division of Standard & Poor's.

The Fool community is rather bullish on Intuitive Surgical. We typically like to see our stocks rated at four or five stars. Anything below that is a less-than-bullish indicator. I highly recommend you visit Intuitive Surgical's stock pitch page to see the verbatim reasons behind the ratings.

Here, short interest is at a high 7.3%. This typically indicates that large institutional investors are betting against the stock.

The last metric I like to look at is the current ratio, which lets investors judge a company's short-term liquidity. If Intuitive Surgical had to convert its current assets to cash in one year, how many times over could the company cover its liabilities? As of the last filing, Intuitive Surgical has a current ratio of 5.20. This is a healthy sign. I like to see companies with current ratios greater than 1.5.

Finally, it's highly beneficial to determine whether Intuitive Surgical belongs in your portfolio -- and to know how many similar businesses already occupy your stable of investments. If you haven't already, be sure to put your tickers into Fool.com's free portfolio tracker, My Watchlist. You can get started right away by clicking here to add Intuitive Surgical.

The final recap


Intuitive Surgical has failed just one of the quick tests that would make it a sell. This is great, but does it mean you should hold your Intuitive Surgical shares? Not necessarily. Just keep your eye on these trends over the coming quarters.

If you haven't had a chance yet, but sure to read this article detailing how I missed out on more than $100,000 in gains through wrong-headed selling.

Jeremy Phillips does not own shares of the companies mentioned.

Intuitive Surgical is a Motley Fool Rule Breakers recommendation. Stryker is a Motley Fool Inside Value selection. Try any of our Foolish newsletter services free for 30 days. True to its name, The Motley Fool is made up of a motley assortment of writers and analysts, each with a unique perspective; sometimes we agree, sometimes we disagree, but we all believe in the power of learning from each other through our Foolish community. The Motley Fool has a disclosure policy.