George Soros didn't amass his estimated net worth of more than $25 billion by making bad stock picks. Through the years, the billionaire investor has poured money into plenty of huge winners.

This year is no exception. These five best-performing Soros stocks have generated gains of at least 46% so far in 2017: Extreme Networks (EXTR -0.72%), Wayfair (W 2.97%), MakeMyTrip Limited (MMYT 4.23%), Tesla (TSLA 2.99%), and Genco Shipping & Trading (GNK 0.43%). Here's how George Soros racked up huge returns from these stocks this year.

Businessman pointing to line graphs going up

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Extreme Networks: Acquisitions and earnings powering the stock

Extreme Networks stock has soared nearly 85% year to date. The networking hardware and software provider has had several catalysts that propelled its share price higher over the past few months.

In early March, Extreme Networks received a boost after announcing that it planned to acquire the networking business of Avaya, which filed for chapter 11 bankruptcy. Later in the month, the stock jumped again on an acquisition -- this time with Extreme Networks announcing that it was buying the data center technology business of Brocade Communication Systems. Most recently, the share price shot up after the company reported strong third-quarter earnings on May 4.

Wayfair: Beating expectations

Wayfair's share price started off 2017 with some nice, but unspectacular, gains. The online home furnishing retailer's CEO reassured investors that consumer spending appeared to be stronger than thought earlier. By late April, Wayfair stock was up more than 30%. Then the company reported its first-quarter results on May 9, prompting its share price to take off. Wayfair stock is now up more than 80% in 2017.

What excited investors so much about Wayfair's first-quarter update? The company reported a loss for the quarter, but it was much better than analysts expected. Revenue grew robustly. Even better, Wayfair projected higher revenue for the second quarter than Wall Street was modeling. 

MakeMyTrip: Making Soros' year great early on

MakeMyTrip stock generated a big return for George Soros early in the year, with shares up more than 50% by the end of January. The India-based online travel company's stock price is now up more than 70% year to date.

The early success for the stock came in part from MakeMyTrip's announcement in January that it had completed its merger of the ibibo Group. This merger created one of the largest travel groups in India. MakeMyTrip also reported strong revenue and earnings growth for the first quarter. The momentum from these announcements kept the stock moving higher throughout the following months, even though MakeMyTrip's shares pulled back in May after the company announced an equity financing round.

Tesla car

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Tesla: Driving higher on good news

Tesla stock is up more than 50% so far in 2017. And that's after a significant drop in late February after the innovative car company reported strong financial results but failed to satisfy investors and after receiving a downgrade from Goldman Sachs

Overall, though, the news has been quite good for Tesla this year. The company announced that it's expanding its charging network to more than 10,000 Superchargers by the end of 2017. Tesla also provided an update stating that it will unveil its first electric semi truck in September. 

Genco Shipping & Trading: Thank-you cards needed for Wall Street firms

Perhaps the most unlikely winner among George Soros' best-performing stocks of 2017 is Genco Shipping & Trading. The shipping company appeared to be fighting for survival earlier in the year, but the stock has gained more than 45% year to date. 

How did Genco do it? To paraphrase the Beatles, with a little help from its friends. Wall Street investment bank Morgan Stanley said in March that dry bulk shipping stocks were ready to rebound. Despite a dismal earnings report from Genco, other Wall Street firms said that its share price was destined to go higher. And it did, thanks to their glowing projections. 

Another common denominator

There's one other thing that these five stocks have in common other than being top performers for George Soros in 2017: They're all losing money.

Several of them are improving from a financial perspective, though. Still, I wouldn't count on any of these stocks being at the top of Soros' list after this year (although Tesla continues to practically defy gravity with its sky-high valuation). Finding stocks of companies with solid business models and growing earnings is probably the better option for investors who aren't billionaires yet.