Cramer homework stock gains 300% since May

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(Click for video linked to a searchable transcript of this Mad Money segment)

Sometimes Jim Cramer tells a caller that he needs to do homework before he can make a decision on a stock. And he's not kidding.

Following is Cramer's research or homework on stocks recently called to his attention by investors who watch the TV show.

Nektar Therapeutics

On September 17th, Ken in New Jersey asked about Nektar Therapeutics.

"Shares fell 21% on Friday after Nektar announced that an important clinical trial of their drug for chronic pain missed its primary endpoint," Cramer said.

Is the setback a reason to run or should you buy the dip?

"Wait for the dust to settle," Cramer said. "This is a serious blow, but the company still has the rights to five drug candidates in phase 3 trials, and they're having an R&D day on October 8th. See what comes out of the meeting, then make a decision."

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GT Advanced Technologies

On September 26th John in Nevada called about GT Advanced Technologies.

Cramer did some digging and found that the stock advanced about 30% in less than a month due to reports that the new iPhone and Samsung's smart watch had incorporated some of GT's technology.

"While these are both positives, they're not home-run opportunities," Cramer said. Given the recent move, I think you need to wait for a pullback in GTAT before you even consider buying it."

And Cramer sees other reasons to like this stock.
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On Friday September 13th, Bob in New York asked about .

"Since May, it's rallied 338%," Cramer said. "Yet even up here, I think Insys trades at a reasonable valuation, and it also looks to me like a viable takeover target. If you already own Insys, I suggest ringing the register on some of your position after this magnificent run, but then let the rest ride because the opportunity here is far from over."

"In fact, I intend to do a further deep dive on this one if heat from Washington melts the market. Yep, I like it that much," added Cramer.


On Monday September 16th Ray in Michigan asked about .

"Cyan is a recent, and fairly disappointing, telecom equipment IPO," Cramer said. "It looks like investors were disappointed with the guidance and the product mix from its first quarterly report as a public company. The first report out of the gate is always important, and when a newly-minted IPO blows it, the stock is going to have to spend some time in the penalty box. We need to see a good quarter here before I'd be willing to circle back."

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