Some stocks are one-hit wonders, making a big splash when they first appear, then quickly fizzling into obscurity or oblivion. But for other stocks, that initial big move is only a preview for even bigger and better gains to come.

Today, we've listed three stocks that made some of the biggest upward moves over the past month, which we'll pair with the ratings issued by our Motley Fool CAPS community. The higher each stock's rating, the greater CAPS members' faith in that company's ability to keep on beating the market.

Stock

1 Month  % Change

CAPS Rating 
(out of 5)

Rediff.com (Nasdaq: REDF)

73.7%

*

ImmunoGen (Nasdaq: IMGN)

48.8%

****

Deer Consumer Products (Nasdaq: DEER)

46.6%

*

Source: FinViz.com; 1 Month % change from April 1 to May 3.

Let's see why the CAPS community thinks some of these companies might continue to outperform the market.

A mighty temblor
Even though Indian Internet portal Rediff.com is one of the top performers over the past month, it was actually quite a bit higher a couple weeks ago before Sify Technologies (Nasdaq: SIFY) disappointed the market with its earnings report. The two have been walking in lockstep lately, with potential for Internet infrastructure investments on the subcontinent expected to benefit both of their respective businesses. For example, when Rediff announced a Groupon-like deals service, the stocks jumped (and caused a corresponding drop in Travelzoo's (Nasdaq: TZOO) stock).

While I had initially bought into the investing thesis that both Rediff and Sify would benefit from greater spending and support, there was just too much froth developing as the slightest pronouncement sent the stock's higher. I subsequently closed out my CAPS rating on both stocks, but didn't also market it down as All-Star TMFUltraLong did who figured Rediff had reached a peak.

I know anything relating to social media is hot, but this is getting a little ridiculous. Rediff.com is still somewhere in the ballpark of a year away from turning a profit by my best guestimates. Instead, I'm just going to follow the pattern here and sell at the top end of the channel.

Let us know on the Rediff.com CAPS page or in the comments section below whether the portal is still open to growth.

Secure in the knowledge
Biotech ImmunoGen is finding success licensing its TAP platform technology -- used for attaching tumor-targeting antibodies to agents that kill the cell once they're inside -- to pharmaceuticals and drugmakers like Amgen (Nasdaq: AMGN), Biogen Idec, and Sanofi.

Rival Seattle Genetics (Nasdaq: SGEN), however, is gaining traction in the space after the FDA denied ImmunoGen partner Roche an accelerated application for its breast cancer therapy trastuzumab-DM1, though a case can easily be made for adding both biotechs to your portfolio. But Roche recently announced that T-DM1 met key goals in a midstage study, and ImmunoGen's shares soared on the news. CAPS member irishred1 admits the higher price makes the stock expensive, but not as expensive as it's going to be in the future.

High premium now but still worth it- gamechanging breast cancer drug about to get approved with more in the pipeline. I think SGEN's ADCs are better, but this one still looks like a worthwhile play if share price dips

Add ImmunoGen to the Fool's free portfolio tracker to see if the plans for this biotech pan out.

Should I stay or go?
Kitchen gadget maker Deer Consumer Products has come out swinging against allegations that it is yet another fraud among small-cap Chinese stocks. After a short seller maligned the company accusing it of fraud, a law firm immediately emerged and filed a class action lawsuit, basing the case on the purported facts. But Deer not only refuted the allegations, it also let the law firm filing the lawsuit know it will seek sanctions against it if it doesn't withdraw the frivolous lawsuit.

Now this could just be a lot of posturing on Deer's part, but it notes that Seeking Alpha, which originally published the case against them, withdrew certain aspects of the article, and the stock has rebounded strongly since the drop, rising 68% from those lows.

The CAPS community remains wary though, with 45% of those rating the Chinese company to underperform the market. Let us know your thoughts on its future on the Deer Consumer Products CAPS page and by adding it to the Fool's free portfolio tracker.

Shake, rattle, and roll
With these stocks shaking the market this past month it pays to start your own research on them at Motley Fool CAPS. Read a company's financial reports, scrutinize key data and charts, and examine the comments your fellow investors have made all from a stock's CAPS page.