Price-fixing is an agreement between competitors to increase, fix or maintain the price at which their goods or services are sold. Competitors do not have to agree to charge exactly the same price, nor that any competitor in a given sector joins the conspiracy. Price-fixing can take many forms and any agreement restricting price competition is against the law. Other examples of price agreements include: repeated purchases can increase the likelihood of collusion, as sellers can familiarize themselves with other bidders and allow future contracts to share the plant. The more standardized a product is, the easier it is for competing companies to agree on a common price structure. It is much more difficult to agree on other forms of competition, such as design, features, quality or service. Since bid manipulation is difficult to detect, any unusual offer agreement reached in consultation or in concert may give rise to suspicions of bid manipulation. Some models may give rise to a suspicion of collusion which is as follows: bid manipulation or collusive manipulation is one of the horizontal agreements, it is an illegal practice, it occurs when two or more competitors or bidders collude and act together to maintain the amount of the offer at the predetermined level and agrees that in reality they will not compete for a specific offer. Market allocation or allocation regimes are agreements by which competitors share markets. In these systems, competing companies assign customers or types of customers, products or territories to each other. For example, a competitor may sell certain customers or certain types of customers or offer them on contracts they lease.

In return, he or she will not sell or offer to customers assigned by customers assigned to other competitors. In other systems, competitors agree to sell only to customers in certain geographic areas and refuse to sell customers in geographical areas assigned to conspiracy companies or to deliberately sell high prices. The offence of manipulating the offer is committed only if the person soliciting the offers or offers is not informed in advance of the agreement reached between the parties. Bid manipulation occurs when two or more people agree that one or more of them will do so in response to a tender or tender: an example of a large case of bid manipulation in the United States was described by Gilbert Geis in his classic article (1967) on heavy suitcases of electrical appliances from 1961. In these cases, all major generators of power generation units conspired to manipulate offers to sell equipment to the Tennessee Valley Authority (TVA) from the 1940s to the 1960s. Business leaders, such as Westinghouse and General Electric, would meet regularly to determine which company would make the profit offer and what price each company would offer. The conspiracy cost TVA millions of dollars on what it should have paid had there been no collusion in the market. The plot collapsed when TVA received two identical offers for the same contract. TVA contacted the U.S. Department of Justice`s Department of Understanding, which has developed criminal and civil proceedings against companies and their executives. The companies have pleaded guilty, as have some executives. Some of the executives served short prison sentences and companies paid fines.

However, as Geis said, the fines imposed on General Electric were equivalent to a person who had to pay a parking fine of 2 U.S. dollars. In addition to a penalty, a company or person convicted of violating the Sherman Act may be ordered to reimburse victims for all surcharges. Victims of bid manipulation and price agreements may also claim civil recovery of up to three times as much damages. There are several frequent red flags that could indicate that a tender or tender could be an objective of bid manipulation: while the handling systems