Annexes Annexe 1: illustration of the oligopoly in economic terms We can illustrate this: The profit in each company is determined by the functions below: Company Kellogs - Pr1= Q1.p1 - Q1.c1 Company General Mills - Pr2= Q2.p2 - Q2.c2 Company Philip Morris - Pr3= Q3.p3 - Q3.c3 Companies associated - Q = q1+ q2+ q3, p, c, Pr In an imperfect oligopoly market when companies decide to make a trust, or to organize to obtain lower costs, prevent the entry of other competitors, etc., we can observe a tendency of equalization of costs, and a degree of monopoly formation. The total profit of monopoly will always be greater than the total profits of the oligopoly (total earnings of all companies). Pr= (q1 + q2 + q3).p - (q1+ q2 + q3).c Pr1+Pr2+Pr3 < Pr In this case, each company will get a higher profit than if they were in the normal imperfect oligopoly, and the individual profit will depend on each production quantity, so Kellogg get a bigger share after General Mills and then Philip Morris. This way, they avoid the entrance of others competitors. Like all trusts, cartels and other illegal practices tend to increase product prices, and thus harm consumers, the organs antitrust act trying to inhibit such practices, as the case with the FTC. Annexe 2 : Cost breakdown Cereals {draw:frame} Annexe 3 : Comment expliquer que la stratégie des concurrents ait marché ? {draw:rect} {draw:rect} {draw:rect} Les deux groupes sont proches car les produits proposés sont relativement proches et les gammes de produits proposés sont imbriquées. {draw:rect} {draw:rect} {draw:rect} {draw:frame} {draw:rect} {draw:rect} Annexe 4 : Présentation de l’évolution des parts de marché (en %) des différents acteurs du secteur des céréales