The nation’s leading hedge fund managers tend to target mid-to-large-sized companies. An investment in small caps often requires too much trading finesse, and too little returns, to be worthwhile. Yet it’s always intriguing to spot that rare moment when big game hunters go after small targets.

#-ad_banner-#Oftentimes, these smaller companies offer the kind of compelling combination of growth and value that even the top fund managers can’t ignore. Here’s a look at three small companies that the nation’s top guru investors have bought into.

Chicago Bridge & Iron Co. NV (NYSE: CBI)
This infrastructure builder sported a mid-cap valuation roughly a year ago, exceeding $10 billion. A subsequent sell-off, which has cut the market value by more than half, threatens to send CBI into the small-cap camp. The dramatic plunge in shares has caught the eye of activist investor David Einhorn. The fund manager’s firm, Greenlight Capital, bought $150 million of CBI stock in the fourth quarter of 2014, though a 15% drop from his $49.25 buy-in price means that stake is now worth a bit less.

Notably, seven other gurus also established new positions in CBI during the most recent quarter, as tracked by gurufocus.com. Warren Buffett’s Berkshire Hathaway, Inc. (NYSE: BRK-A) has been the company’s largest shareholder for several years.

CBI has been beset by concerns about aggressive accounting procedures related to its 2012 acquisition of rival The Shaw Group. Einhorn, who has a strong reputation as a forensic accountant, has presumably looked at (and grown comfortable with) that issue. Investors have also been dumping shares on concerns about CBI’s exposure to the energy sector.

For context, management just issued 2015 earnings per share gudiance, or EPS, in the $5.55-6.05 range, ahead of the $4.98 a share earned in 2014. Still, Einhorn, Buffett and others are focusing on this stock for long-term positioning, and not just near-term EPS

In recent years, U.S. infrastructure spending has been weak. Bridge, road, power plant and other essential projects should see an increase in capital flows in coming years, a direct catalyst for CBI.

At current levels of business, CBI generates roughly $1 billion in annual earnings before interest, taxes, depreciation and amortization, or EBITDA. Analysts at DA Davidson figure shares will more than double to $88, based on a target 2015 EBITDA multiple of nine (on an enterprise value basis).

RetailMeNot, Inc. (Nasdaq: SALE)
Steven Cohen, who was forced to liquidate his SAC Capital Advisors hedge fund in 2014, is now investing through another investment firm — Point 72 Asset Management. That firm holds an eclectic mix of small-, mid- and large-cap stocks, including a new three million share stake in this online retailer. He’s trying to bottom fish, as shares have slid to a recent $17, from a 52-week high of $48.

Part of that sell-off is attributable to a decline in sales growth. Sales increased 45% or more every year through 2013, but then growth slowed to 25% in 2014 and will likely slow to single-digits this year. The company is transitioning its online coupon business model from a desktop focus to a mobile focus, which means the company is investing heavily in its sales force. That effort will keep EPS relatively flat at around $1 this year, according to management.

Yet, investors may be overlooking the fact that this business is quite healthy: RetailMeNot generated $94 million in EBITDA in 2014 and has nearly $200 million in net cash, which is enabling the company to pursue a new $100 million share buyback program. Steven Cohen is probably forward looking; expecting SALE to benefit from the long-term migration away from print-based coupons and toward online coupons.

LendingClub Corp. (NYSE: LC)
George Soros is known for making bit bets (such as a legendary bet against the British pound in the 1990s). These days, he still focuses on big targets, owning shares of companies like The Dow Chemical Co. (NYSE: DOW) and United Continental Holdings, Inc. (NYSE: UAL). He’s also focused on this upstart financial services firm.

LendingClub connects investors with people and small businesses that need to borrow (many of whom may not qualify for traditional banking loans). Such loans often replace higher-interest credit card debt. The firm doesn’t focus on sub-prime borrowers, per se: The minimum credit score is 660 and the average is 700. Yet the site offers more relaxed lending standards than traditional banks. Of course, that brings a risk that such loans may eventually have high default rates, as the Wall Street Journal recently noted.

George Soros took a 4.5 million share stake in the company in December 2014, either right at the time of its IPO, or soon thereafter. Shares slumped more than 10% this week after the company issued inline results and guidance, but Soros likely looks at this business model as potentially transformative over the long haul and not merely a timely, value-oriented trade

Risks To Consider: These companies occupy a tiny fraction of the portfolios held by these gurus. As such, they may not hold these positions as long as core blue-chip holdings if they sense it is time to move to safer, larger stocks.

Action To Take –> All three of these companies aim to capture big picture themes: infrastructure spending, online couponing, alternative banking. The gurus behind them are betting that these companies can deliver significant upside from currently depressed levels.  

Looking for more growth potential? My colleague Andy Obermueller devotes his time to identifying game-changing trends and the companies. This has led readers to investments that went on to gain triple-digits. Recently, Andy has been talking about the profit potential for Apple’s newest technology Apple Pay — and more importantly the company’s key suppliers. If you haven’t heard about this opportunity yet, then I urge you to check out his comprehensive report on how to profit from this technology, by clicking here.