Competition is the cold-blooded stock killer

Want to know how to kill a stock price quickly? Look no further than price competition.

As soon as you start to see competition, Jim Cramer recommends putting on your running shoes and hightailing it away from the stock.

Competition is great for the consumer though, right? Just walk into a Best Buy showroom and pull out a competitor's ad with a lower price, and they will match it. That's good for the consumer who gets to save money, good for Best Buy to retain customers from buying elsewhere online but bad for the stock price.

For instance, take Cramer's long-standing biotech fave Gilead. It had a monopoly on the Hepatitis C market, with a high price tag of $80,000 a year. This brought in billions of dollars in sales, at the patient's expense.

That monopoly fizzled quickly when the FDA approved AbbVie's hepatitis C drug, which will be sold at a much lower price than Gilead's. That's why Gilead's stock dropped more than 14 percent Monday.

Facebook headquarters
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What's more, this situation could become the new model for biotech. The whole group, which has been on a good run, could be under pressure until further notice.

"I think that you have to back away from the group for now and let it come in. Why bother to be a hero in a sector that's already run up so much? Take a breather, take some gains. We can always revisit," the "Mad Money" host said.

The competition disease has spread into other industries as well. Autos can't seem to gain traction, as there are just too many of them and the price cuts are everywhere.

Or how about Amazon? For years, Amazon has been cutting costs to the bricks and mortar retailers. As a result, the retailers have adopted an approach that allows customers to order online and make returns at the nearest store. That limits what Wall Street will pay for Amazon.

On the flip side, companies with little or no competition are thriving. Many semiconductor companies have merged, giving them pricing power over customers. In the airline industry, the skies are clear for United Continental, American Airlines, Delta and Spirit. They are able to fly on routes that were previously clogged with competition.

"I like Facebook because it has a monopoly on yourself, or at least your digital self. What a fantastic business with a giant moat around it, which is what Warren Buffett's always talking about when he looks for his next investment," Cramer said.

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Ultimately, when a group goes from having no competition to having competition—investors will pay less for the stock.

Keep your eyes open. If you like a specific industry and you see two companies butting heads, put those running shoes on. In Cramer's opinion, the havoc happening in the biotech space is just too great to ignore.

"I say take profits or wait on the sidelines until you're sure that the Gilead/AbbVie fight for market share is an anomaly, and not the new normal."

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