There's never a shortage of losers in the stock market. Let's take a closer look at five of this past week's biggest sinkers.

Company

Jan. 24

Weekly Loss

Amarin (NASDAQ:AMRN)

$1.71

25%

Organovo (NASDAQ:ONVO)

$9.12

18%

Orion Energy Systems (NASDAQ:OESX)

$6.02

18%

3D Systems (NYSE:DDD)

$79.87

12%

Sify (NASDAQ:SIFY)

$1.98

11%

Source: Barron's.

Let's start with Amarin. The FDA shot down Amarin's appeal of the agency's rescinding of Special Protocol Assessment to expand the use of its triglyceride-lowering drug, Vascepa. Amarin plans to keep trying, but that will take time and the chances of success may be slim.

Organovo took a hit after Citron Research blasted the company's valuation on CNBC's Fast Money. Calling Organovo's goal of bio-printing organs "ridiculous," Citron's Andrew Left detailed a warning out of Sweden's SEC equivalent on cold callers who are promoting the stock. He argues that Organovo's weak institutional ownership at just 8% makes it easy to pump the shares. There may be some substance to Left's knocks, but the outcome here will ultimately be up to the company, which expects a major viability test to play out this year.

Orion Energy Systems fell every single trading day. The provider of energy management solutions had wrapped up the prior week by filing a universal shelf registration statement with the SEC to offer as much as $75 million worth of securities. Investors don't like the eventual dilution.   

3D Systems probably printed parachutes for shareholders after the 3-D printing leader got a downgrade from Credit Suisse. It also didn't help that Citron Research issued another negative note on 3D Systems on Friday, a move that sent 3D Systems and a couple of its smaller peers to double-digit percentage losses on the week. Citron has a $56 near-term price target on the shares, warning that it could head even lower after that.

Sify slumped after posting quarterly results on Tuesday morning. Results out of the India-based provider of IT solutions weren't bad. Revenue climbed 21%, and it reversed a year-ago loss by posting a quarterly profit. However, the market was apparently still unimpressed.