Most successful entrepreneurs say hard work and talent are necessary to make money legally. However, some individuals and companies operate where the line between legal and illegal business is blurred. Here are five ways to make money that should be outlawed.

Trading on 'not publicly known' information

Some hedge funds and investors make trades based on information they have obtained through the Freedom of Information Act, according to a 2015 study by researchers from the University of Maryland and the University of Melbourne. Fees involved in making a Freedom of Information Act request range from a few dollars to several thousand.

Online make-money multilevel marketing

Jon M. Taylor offers consulting services for attorneys, financial advisers, regulators, and others who confront problems dealing with multilevel marketing companies. Taylor told the Chicago Tribune that he has yet to find a good multilevel marketing company. "There is no more unfair and deceptive practice than multilevel marketing," he told the paper.

Greyhound racing

Although dog racing is legal in some states, animal cruelty is not. Many dogs that race endure shocking injuries and unacceptable living conditions, and are denied proper nutrition and veterinary care, according to the American Society for the Prevention of Cruelty to Animals. ASPCA says the sport is legal in Alabama, Arizona, Arkansas, Florida, Iowa, Texas and West Virginia.

Flash trading

Investopedia defines flash trading as employing "highly sophisticated high-speed computer technology to allow traders to view orders from other market participants fractions of a second before others in the marketplace." "Flash trading is an outrageously profitable practice that provides absolutely no benefit to the public," said Gary Duell, owner of Duell Wealth Preservation

Political lobbying

Some members of Congress have an incentive to acquiesce to lobbyists out of self-interest, perhaps to increase the likelihood of lucrative consultancy deals once they leave office. House members must wait a year before working as a lobbyist, and senators must wait two years. Legislation was proposed last year to prevent retired members of Congress from ever becoming lobbyists.

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