Cartels and anti-competitive agreements

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What are cartels and how do they affect consumers?

Hardcore cartels (when firms agree not to compete with one another) are the most serious violations of competition law.  They injure customers by raising prices and restricting supply, thus making goods and services completely unavailable to some purchasers and unnecessarily expensive for others. 

The categories of conduct most often defined as hardcore cartels are:

  • price fixing
  • output restrictions
  • market allocation
  • bid-rigging (the submission of collusive tenders)
Hardcore cartel prosecution is a priority policy objective for the OECD. Increasingly, the prohibition against hardcore cartels is now considered to be an indispensable part of domestic competition law.

Challenges in detecting hardcore cartels

Cartels are very difficult to detect.  They can involve many firms in the industry and customers are rarely in a position to detect the existence of a cartel.  Antitrust enforcers should be helped in their ability to detect cartels by various means and instruments, the most effective being leniency programmes.  These programmes provide immunity or reduction in sanctions for cartel members that co-operate (or ‘whistleblow’) with competition enforcers.  Leniency programmes have been adopted by most OECD countries and have been instrumental in increasing the success rate of the detection of cartels.

The best outcomes are secured by deterring firms from forming cartels in the first place.  Strong sanctions are therefore a fundamental component of an effective antitrust enforcement policy against hardcore cartels.  An important supplement to fines against organisations for cartel conduct is sanctions against individuals for their participation in the conspiracy. These sanctions can take the form of substantial administrative fines or, in some countries, the criminal sanction of imprisonment.  The prospect of incarceration can be a powerful deterrent for businesspeople considering entering into a cartel agreement.

But are all agreements among competitors harmful? 

Some horizontal agreements between companies can fall short of a hardcore cartel, and in certain cases may have beneficial effects.  For example, agreements between competitors related to research & development, production and marketing can result in reduced costs for companies, or improved products, the benefits of which are passed on to consumers. The challenge for competition authorities is how to assess these agreements, balancing the pro-competitive effects against any anti-competitive effects which may distort the market.

For further information related to the OECD work on cartels and anti-competitive agreements, please contact us at



Access our new database of international cartels with over 200 references since 2012 from approximately 50 jurisdictions.

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» List of all policy roundtables on cartels 


Latest roundtables on cartels

Common ownership by institutional investors and its impact on competition, 2017

Safe harbours and legal presumptions in competition law, 2017

Algorithms and collusion, 2017

Big data: Bringing competition policy to the digital era, 2016

Cartels involving intermediate goods, 2015

Competition and cross-platform parity agreements, 2015

Oligopoly markets, 2015

Competition and the use of markers in leniency programmes, 2014

OECD inventory of international co-operation agreements on competition, 2014

Enhanced Enforcement Co-operation, 2014

Ex officio cartel investigation and the use of screens to detect cartels, 2013

Competition and Procurement: Key findings, 2011

See also

OECD 2019 Recommendation concerning Effective Action against Hard Core Cartels

Review of the 1998 OECD Recommendation concerning Effective Action against Hard Core Cartels, 2019

Individual and Collective Private Enforcement of Competition Law: Insights for Mexico, 2018 

Hard Core Cartels: Third Report on the Implementation of the 1998 Council Recommendation, 2005

Formal Exchange of Information between Competition Authorities in Hard Core Cartel Investigations, 2005


Fighting Bid Rigging in Public Procurement  

Bid rigging involves groups of firms conspiring to raise prices or lower the quality of the goods or services offered in public tenders. Although illegal, this anti-competitive practice continues to cost governments and taxpayers billions of dollars every year across OECD countries.

The OECD Guidelines for Fighting Bid Rigging in Public Procurement were developed to help governments design the procurement process so as to reduce risks of bid-rigging and to detect conspiracies during the process.

Countries like Mexico and Colombia have already partnered with the OECD to improve procurement practices and step up their fight against bid-rigging. 

» Read more about the Mexico-OECD partnership and related reports.

» See the 2014 report on Fighting Bid Rigging in Public Procurement in Colombia.


More on the OECD project on fighting bid-rigging can be found at


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