Very simply, that's called a conspiracy to commit fraud with investment instruments. http://www.merriam-webster.com/dictionary/conspiracy
Is that a common and viable strategy?
It happens, though because it is illegal, it's probably (hopefully) not common. And since it's illegal, generally speaking, people view it as not very viable.
Are laws protecting future investors against this kind of games?
Securities Fraud https://en.wikipedia.org/wiki/Securities_fraud
Securities fraud, also known as stock fraud and investment fraud, is a
deceptive practice in the stock or commodities markets that induces
investors to make purchase or sale decisions on the basis of false
information, frequently resulting in losses, in violation of
Pump and Dump: https://en.wikipedia.org/wiki/Pump_and_dump
Pump and dump" (P&D) is a form of microcap stock fraud that involves
artificially inflating the price of an owned stock through false and
misleading positive statements, in order to sell the cheaply purchased
stock at a higher price.
Insider Trading: https://en.wikipedia.org/wiki/Insider_trading
Insider trading is the trading of a public company's stock or other
securities (such as bonds or stock options) by individuals with access
to nonpublic information about the company. In various countries,
trading based on insider information is illegal.
And: The regulatory and enforcement agency is the U.S. Securities and Exchange Commission
The U.S. Securities and Exchange Commission "holds primary
responsibility for enforcing the federal securities laws, proposing
securities rules, and regulating the securities industry, the nation's
stock and options exchanges, and other activities and organizations,
including the electronic securities markets in the United States."