Market manipulation is a deliberate attempt to interfere with the free and fair operation of the market and create artificial, false or misleading appearances with respect to the price of, or market for, a security, commodity or currency. Market manipulation is prohibited in most countries, in particular, it is prohibited in the United States under Section 9(a)(2)[1] of the Securities Exchange Act of 1934, in Australia under Section 1041A of the Corporations Act 2001, and in Israel under Section 54(a) of the securities act of 1968. The Act defines market manipulation as transactions which create an artificial price or maintain an artificial price for a tradeable security. Market manipulation is also prohibited for wholesale electricity markets under Section 222 of the Federal Power Act[2] and wholesale natural gas markets under Section 4A of the Natural Gas Act.[3]
Examples
Pools: "Agreements, often written, among a group of traders to delegate authority to a single manager to trade in a specific stock for a specific period of time and then to share in the resulting profits or losses."[4]
Churning: "When a trader places both buy and sell orders at about the same price. The increase in activity is intended to attract additional investors, and increase the price."
Stock Bashing: "This scheme is usually orchestrated by savvy online message board posters (a.k.a. "Bashers"
who make up false and/or misleading information about the target company in an attempt to get shares for a cheaper price. This activity, in most cases, is conducted by posting libelous posts on multiple public forums. The perpetrators sometimes work directly for unscrupulous Investor Relations firms who have convertible notes that convert for more shares the lower the bid or ask price is; thus the lower these Bashers can drive a stock price down by trying to convince shareholders they have bought a worthless security, the more shares the Investor Relations firm receives as compensation. Immediately after the stock conversion is complete and shares are issued to the Investor Relations firm, consultant, attorney or similar party, the basher/s then become friends of the company and move quickly to ensure they profit on a classic Pump & Dump scheme to liquidate their ill gotten shares
Examples
Pools: "Agreements, often written, among a group of traders to delegate authority to a single manager to trade in a specific stock for a specific period of time and then to share in the resulting profits or losses."[4]
Churning: "When a trader places both buy and sell orders at about the same price. The increase in activity is intended to attract additional investors, and increase the price."
Stock Bashing: "This scheme is usually orchestrated by savvy online message board posters (a.k.a. "Bashers"
who make up false and/or misleading information about the target company in an attempt to get shares for a cheaper price. This activity, in most cases, is conducted by posting libelous posts on multiple public forums. The perpetrators sometimes work directly for unscrupulous Investor Relations firms who have convertible notes that convert for more shares the lower the bid or ask price is; thus the lower these Bashers can drive a stock price down by trying to convince shareholders they have bought a worthless security, the more shares the Investor Relations firm receives as compensation. Immediately after the stock conversion is complete and shares are issued to the Investor Relations firm, consultant, attorney or similar party, the basher/s then become friends of the company and move quickly to ensure they profit on a classic Pump & Dump scheme to liquidate their ill gotten shares 
