Antitrust law mainly focuses on market power – both individually or jointly with competitors, a company with enormous market power is a monopoly and does typically the following;
Price fixing – this happens when the price of a product is controlled/set by one market player deliberately without letting the market forces (demand and supply) fix it naturally. Although several firms may determine the price jointly. This action does not benefit small businesses because they have no control over the market forces. These laws ensure there is fair competition in the market to provide profitability for every market player.
Negation to deal – monopolies just like other competitors may choose on whom to do business with. But in the case if they use their market supremacy then small businesses will not be having a fairground to deal business in, these laws regulate market dominance by enhancing mergers and acquisitions to enable stability of small businesses.