Shares of Intel(INTC) - Get ReportIntuitive Surgical(ISRG) - Get Report  and Yahoo! (YHOO)  were all making significant moves Wednesday after the three companies announced quarterly results Tuesday.

Let's take a look at what each company reported and whether you should buy its stock, sell it or hold it. Later we'll tell you about a few stocks you could be buying today.

Shares of Intel had slumped 5.6% by about 11:30 a.m. EDT Wednesday. The chipmaker said third-quarter revenue rose 9.% year over year to $15.8 billion, topping the Wall Street estimate for $15.58 billion. Adjusted earnings per share were 80 cents, beating the analyst consensus for 73 cents. Net income rose to $3.38 billion, or 69 cents a share, up from $3.11 billion, or 64 cents a share, a year ago. Intel saw both its PC business and cloud storage business increase.

Despite all the good news, Intel gave weaker-than-expected guidance for the fourth quarter, which is why the stock is trading lower. Management believes revenue in the current quarter will come in around $15.7 billion, below the $15.86 billion Wall Street had been expecting.

Intel has been in a tough spot over the last few years as tablets and smartphones extend PC upgrade cycles from every few years to until a PC stops working. Today is not a terrible time to buy Intel, due to the stock being sold for a discount, but it is also hard to make a strong case as for why Intel will be a market-beating stock moving forward.

Shares of Yahoo! were up 2.4% shortly after noon EDT Wednesday. The company Tuesday reported third-quarter revenue of $1.31 billion, just higher than the $1.3 billion Wall Street analysts' were expecting.Yahoo! pays fees to partner websites, however, and if you back out those fees, Yahoo! really brought in only $857.7 million, down from $1 billion a year earlier.

EPS came in at 17 cents on $162.8 million of net income, up from $76.3 million, or 8 cents, a year earlier. Excluding items, Yahoo's adjusted EPS was 20 cents, exceeding the 14 cents analysts had expected.

Yahoo! did not hold a conference call or webcast following the earnings release, a decision that has a number of analysts concerned that Verizon's planned acquisition of Yahoo! may be on shaky ground. Since news broke about a massive data breach that affected Yahoo! users, Wall Street and Verizon shareholders have shown increased concern about the acquisition. The breach affected more than 500 million people, and what analysts and investors need to figure out is how that will affect user counts moving forward.

No one should be buying Yahoo! stock today. The quarter was mediocre at best and until the Verizon situation is figured out, the stock is simply too risky.

Investors don't seem to care that Intuitive Surgical posted a 26% year-over-year increase in third-quarter GAAP net income, because shares of the surgical robotics company are down 4.3%. Intuitive Surgical reported revenue of $683 million, a 16% year-over-year increase. Revenue also beat the $650.5 million Wall Street consensus. Net income came in at $211 million, or $5.31 per share, above the $167.3 million, or $4.40, reported a year earlier.

Adjusted EPS was $6.19, well above the $5.14 analysts expected. This figure was helped by a $0.77 tax gain, but even with that backed out, Intuitive Surgical still easily beat the Street's estimate.

The company reported it sold 134 new da Vinci surgical systems, an increase from 117 a year ago. Moving forward, the company expects procedures using da Vinci systems to grow 14% to 15% the full year. Some investors took this growth rate as a negative sign for the company. For a stock that is trading at 40 times past earnings, one would expect growth to be slightly higher than just 15%.

Intuitive Surgical is a difficult stock to value. But today doesn't seem to be the worse place to begin building a position. The company will likely have tough times ahead, but due to its truly ground-breaking technology, it should be able to climb out of any holes it finds itself in.

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Just because you may not want to be buying shares of Intel or Yahoo today doesn't mean you can't buy any stocks right now! Here is a list of seven companies that you will profit from, regardless of what the markets do. But with many calling for a coming crisis, now is the perfect time to make sure you and your portfolio are protected. Each one of these powerful, yet overlooked companies barely notices when the market tumbles. And they'll skyrocket when it rebounds. Get their names here before it's too late.

The author is an independent contributor who at the time of publication owned stock in Intel.