Four Stocks Down More Than 30 Percent Last Week

Last week brought carnage for stocks. The S&P 500 was down about 2.5 percent, but some individual stocks were hit much harder. These four each lost nearly 40 percent of value:

Imperva IMPV- Down 43 Percent

Imperva is a $733 million company that develops, markets and sells services related to data security. It trades an average of 762 thousand shares daily, but volume spiked last week. 2.2 million shares traded on Friday alone.

The company preannounced earnings that disappointed the street. Earnings should come in between $31 and $31.5 million versus the expected $36 to $37 million range. That divergence prompted numerous law firms to start investigating whether the company violated securities law.

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Despite an upgrade to “buy” from Sterne Agee on Friday, the stock has recovered only fractionally.

Gigamon GIMO – Down 38 Percent

Gigamon is a $517 million company that sells products allowing IT professionals to view network traffic. The stock trades an average of 727 thousand shares per day but volume more than doubled this week.

The company reduced its first-quarter revenue forecast from $34 to $35 million to $31 to $31.5 million after it announced that it had lost a contract with one of its large customers.

Despite the bad news, DA Davidson upgraded the stock from “Neutral” to “Buy” based on valuation.

Voxeljet AG VJET- Down 39 Percent

Voxeljet is a $235 million company that provides 3D printers to industrial and commercial customers. Average trading volume is 512 thousand shares daily but Friday, volume spiked to more than five million.

The stock steadily fell all week but plunged 18 percent after announcing that it would sell an additional 3 million shares for $15 per share—19.1 percent below Thursday’s closing price.

The price of these shares sent investors running as they asked why the company would choose to commence a stock sale now. Investors are selling growth stocks as fast as they can.

Datawatch DWCH- Down 39 Percent

Datawatch is a $125 million company that designs and develops software that provides a platform for visually interpreting data. The company was down 29 percent Friday after preannouncing fiscal Q2 results that disappointed the street. The company said that total revenue would be between $7.8 and $8 million, resulting in a Non-GAAP new loss between $3.1 and $3.3 million.

Disclosure: At the time of this writing, Tim Parker had no position in any of the companies mentioned.