According to Wikipedia:
Price gouging is a pejorative term for a seller pricing much higher than is considered reasonable or fair. In precise, legal usage, it is the name of a felony that applies in some of the United States only during civil emergencies. In less precise usage, it can refer either to prices obtained by practices inconsistent with a competitive free market, or to windfall profits. Non-pejorative uses are generally in reaction to what the writer believes is an unjustified restraint on the market.
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I think you might also be interested in what Wikipedia has to say about:
Collusion is an agreement, usually secretive, which occurs between two or more persons to deceive, mislead, or defraud others of their legal rights, or to obtain an objective forbidden by law typically involving fraud or gaining an unfair advantage. It is an agreement among firms to divide the market, set prices, or limit production. It can involve “wage fixing, kickbacks, or misrepresenting the independence of the relationship between the colluding parties.” All acts effected by collusion are considered void.