<P> What amounts to a substantial lessening of, or significant impediment to competition is usually answered through empirical study . The market shares of the merging companies can be assessed and added, although this kind of analysis only gives rise to presumptions, not conclusions . The Herfindahl - Hirschman Index is used to calculate the "density" of the market, or what concentration exists . Aside from the maths, it is important to consider the product in question and the rate of technical innovation in the market . A further problem of collective dominance, or oligopoly through "economic links" can arise, whereby the new market becomes more conducive to collusion . It is relevant how transparent a market is, because a more concentrated structure could mean firms can coordinate their behavior more easily, whether firms can deploy deterrents and whether firms are safe from a reaction by their competitors and consumers . The entry of new firms to the market, and any barriers that they might encounter should be considered . If firms are shown to be creating an uncompetitive concentration, in the US they can still argue that they create efficiencies enough to outweigh any detriment, and similar reference to "technical and economic progress" is mentioned in Art . 2 of the ECMR . Another defense might be that a firm which is being taken over is about to fail or go insolvent, and taking it over leaves a no less competitive state than what would happen anyway . Mergers vertically in the market are rarely of concern, although in AOL / Time Warner the European Commission required that a joint venture with a competitor Bertelsmann be ceased beforehand . The EU authorities have also focused lately on the effect of conglomerate mergers, where companies acquire a large portfolio of related products, though without necessarily dominant shares in any individual market . </P> <P> Competition law has become increasingly intertwined with intellectual property, such as copyright, trademarks, patents, industrial design rights and in some jurisdictions trade secrets . It is believed that promotion of innovation through enforcement of intellectual property rights may promote as well as limit competitiveness . The question rests on whether it is legal to acquire monopoly through accumulation of intellectual property rights . In which case, the judgment needs to decide between giving preference to intellectual property rights or towards promoting competitiveness: </P> <Ul> <Li> Should antitrust laws accord special treatment to intellectual property . </Li> <Li> Should intellectual rights be revoked or not granted when antitrust laws are violated . </Li> </Ul> <Li> Should antitrust laws accord special treatment to intellectual property . </Li>

Brief concept of the development of competition laws in usa and uk