There are, however, some criticisms of a horizontal pricing ban. Some conservative economists argue that horizontal price agreements are not worth considering because they are economically unstable. Each member of a horizontal price agreement has a strong incentive to correct an error, as it secretly offers lower prices to attract a larger proportion of customers. In addition, each market with excessive prices, induced by a horizontal agreement, will quickly attract new entrants and can easily bring prices down to competitive levels. Finally, many economists are skeptical of the ability of courts and prosecutors to distinguish between real price agreements and other complex agreements for legitimate purposes of promoting competition. Corporate distrust of the price cartel is also an obstacle to further manipulation. If all this fails, pricing usually collapses because of the power of large customers to negotiate the price they are willing to pay. Similarly, companies that are not in collusion lose market share and sales if pricing is done with a discount. Since 1997, U.S. courts have divided price fixing into two categories: vertical and horizontal pricing.  Vertical pricing includes a manufacturer`s attempt to control the price of its product in the retail sector.
 At State Oil Co. v. Khan, the U.S. Supreme Court held that vertical price agreements are no longer considered in themselves a violation of the Sherman Act, but that horizontal pricing is still considered an offence under the Sherman Act. Also in 2008, the united States v LG Display Co., United States v. Chunghwa Picture Tubes and United States v. Sharp Corporation. , who were heard in the Northern District of California, agreed to pay a total of $585 million to balance their lawsuits in order to set the prices of liquid crystal panels. This was the second largest amount awarded in history after the Sherman Act.  The fact that all competitors apply the same price or apply the same terms of sale is not, in itself, evidence of a price-fixing conspiracy, since similar prices may in fact result from competition. However, if price increases are announced simultaneously or before a single date by all competitors, there is a high probability of collusion. For example, the FTC has challenged a professional code adopted by a national association of arbitrators that prohibits virtually all forms of advertising and client recruitment.
In an approval agreement with this organization, the rules were changed, so that individual members were not prevented from promoting truthful information about their prices and services. Like cargo, many products are now transported by freight through different channels. If freight prices artificially increase, this will have an impact on the entire supply chain. For example, this will lead to higher prices for goods and services and will have an impact on consumer choice.  For example, the Organization of the Petroleum Exporting Countries (OPEC) is famous for setting oil production volumes to keep oil prices high. It should be noted that not all prices or similar price changes are simultaneous price fixings. These situations are often normal market phenomena. For example, the prices of agricultural products such as wheat are not very different, as these agricultural products do not have characteristics and are substantially identical, while changing only slightly.