Look for opportunities globally. In the United States, there is money in search of opportunity. Internationally, there is opportunity in search of money, so your chances of being able to invest in a top innovator are higher. "Look for the great filters in the region, women and men, and get to know the ecosystem if you have a taste for the risk and the stamina for it," said Christopher Schroeder, a venture investor and the author of "Startup Rising," a book about start-ups in the Middle East.
Dave McClure, who runs the famous Silicon Valley start-up incubator 500 Startups and is also a start-up investor, said that 25 percent of the companies he invests in are now international. He expects that to grow to 50 percent within the next five years.
McClure gave an example of a company he invested in called Viki, which provided video subtitles in foreign languages and which was acquired after four years by Japanese e-commerce giant Rakuten for $200 million.
If you're interested in international investing, you can take two approaches: Network among the angel groups to find venture capital funds working internationally. Or, if you have connection or interest in a particular market, you can do your own on-the-ground reconnaissance and networking.
"They're really quite accessible and not nearly as foreign as you tend to think," said McClure. "They're less than a 24-hour flight. There are modern-day Marco Polos happening in greater and greater numbers."
It's likely that crowdfunders and new technology platforms will broaden their scope to allow international equity investing at some point, too.
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