In 1991 there were about 270 billionaires in the world. Today there are more than 1,600, and 290 were added to the rolls in the past year alone. In other words, more people became billionaires in the past year than there were billionaires in 1991.

A skeptical person might say that’s further evidence the rich are getting richer. A positive, go-getting person would say, “It’s easier to become a billionaire than ever before.” And it is.

I’ve made a comprehensive study of the richest people in history and the present day, and found common ground in many of their wealth secrets, including:

1. Don’t be the best. Be the only

Many experts on personal financial success will exhort you to be the best. They will advise you on routes to self- improvement and personal growth. Business books will tell you how to make your business “great” or “excellent.”

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These are all pretty much dead-ends. The difference between the technology and the finance sectors highlights why: Companies in many sectors are innovative. But companies in the financial sector cannot patent their innovations, so they must look for profits in other ways.

Technology companies are profitable because they have patents; and patents give them miniature monopolies. If any competitor attempts to imitate a technology in a way that is protected by patent, the government will rough them up a bit. This puts a brake on competition, which in turn sets the stage for profitability that lasts.

That’s the wealth secret of the world’s richest man, Bill Gates. When he co-founded Microsoft MSFT, -0.41% such protections didn’t exist. So he had to create them through clever legal contracts. And Gates had one notable advantage in this regard: his father was a lawyer.

2. The worst place to do business is really the best

Most businesspeople are instinctively attracted to the largest, most lucrative markets.

They see a number with a lot of zeros at the end and it overwhelms their common sense. They think that if they can get even a little bit of that huge sum of money, they will be rich. Following this line of reasoning, they conclude that going global is the ultimate achievement of business strategy, because going global increases the number of markets they are in.

Totally wrong. While going for a huge market is tempting, you will be forced to price competitively and probably won’t make much money. You might have a significant share of a huge market, but it won’t be worth much, relatively. It is much better to go for a huge share of a tiny market. There, you can turn the screws.

That’s the wealth secret of the world’s second-richest man, Carlos Slim, who gained monopoly rights to the Mexican telecom market, awarded by the Mexican government. While telecom giants including Vodafone and AT&T were bashing each other in the world marketplace, Slim was taking his dominance of his tiny market to the bank.

3. You’ve got to own it, baby

Property rights are the basis for a wealth secret that appears often on the Forbes Global Rich List. Among the top fortunes in advanced economies, 75% are attributable to either hedge funds or intellectual property rights.

On the broader Forbes list of more than 1,600 billionaires that includes emerging-markets, there is more diversity in how wealth was amassed, but property rights in general nonetheless appear frequently. About 130 of the roughly 1,600 fortunes are in real estate. A further 40 or so are in oil and gas or mining. About 120 are in fashion or retail, where companies often own not only valuable brands but valuable properties. Roughly 65 are in pharmaceuticals or health care, 90 or so are in technology, and about 70 more are in media.

In other words, on a rough estimate, at least a third of these fortunes are due to property rights of some kind. And that is without trying to factor in the wealth gained after the former Soviet Union collapsed, and a lot of valuable assets changed hands in a short period.

What do the habits of billionaires mean for you?

The above three principles have one thing in common: they are techniques for defeating the forces of market competition. These are techniques I have called “wealth secrets.”

The best way to get super-rich is to start a company with a wealth secret. It’s easier than ever to have a new Apple AAPL, +0.18% , for example, because such companies have network effects. The more people who are connected to a network, the more valuable the network. Another network business is social media. Facebook FB, +1.22% and other social media companies tend to natural monopolies very quickly. These companies become dominant and there is only one winner.

If you can’t do that, you can invest in their shares through a couple of unique exchange-traded funds. Market Vectors Morningstar Wide Moat ETF MOAT, +0.44% , follows investment researcher Morningstar’s “Wide Moat Focus Index.” An international version of this strategy, Market Vectors Morningstar International Moat ETF MOTI, -0.37% , was introduced in July and is based on the Morningstar Global ex-US Moat Focus Index.

I don’t 100% agree with Morningstar’s methodology, but essentially, most of what it calls “moats” are what I call “wealth secrets.”

The problem with this approach is that companies with wealth secrets tend to earn millions of dollars in profits year after year, which is the kind of thing that gets noticed on Wall Street. So these stocks are expensive. Morningstar attempts to overcome this problem with a sophisticated valuation algorithm.

But really what an investor needs to do is identify the companies with wealth secrets before they start paying off. That’s not easy, but it’s not impossible: As far as I can tell, that’s what made Warren Buffett a billionaire.

Sam Wilkin is a senior advisor at Oxford Economics and the author of “Wealth Secrets of the One Percent: A Modern Manual to Getting Marvelously, Obscenely Rich.” (Little, Brown).