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Cet article passe en revue différents comportements microéconomiques de stockage et de vente de contrats à terme selon le type de concurrence (parfaite, situation de monopole ou oligopolistique), et selonl’information dont disposent les acteurs. Ces instruments, qui permettent de faire transiter une quantité de bien du présent vers le futur à un prix fixé, et qui diffèrent par leur liquidité, sont à utiliser conjointement afin de stabiliser les prix spots en concurrence parfaite. Lorsque l’information est asymétrique, les agents informés peuvent utiliser le marché à terme pour vendre leur information aux agents non informés, ou pour manipuler les prix. Lorsque les producteurs sont en concurrence oligopolistique, un cartel peut substituer le stockage à la vente à terme afin de réduire la concurrence que lui livre une frange de petits producteurs. Enfin des producteurs peuvent aussi utiliser stockage ou vente à terme pour accroître leur part de marché.

Microeconomic storage and forward trading behaviours: a survey This paper investigates the literature describing the microeconomic behaviour of agents using storage and future contracts, depending on the nature of their information and on the nature of competition. In the price stabilisation theory, even if it may have ambiguous effects on the distribution of prices when conducted by single competitive agents, private storage is needed to strengthen the stabilizing effect of future contracts on price volatility, suggesting that both tools have to be used jointly. When some agents are informed, they may use the future market to sell their information to uninformed agent, or use the forward market to signal the quality of their product when other agents do not observe it. The stabilizing effect of futures markets is still valid in the first case. However together with inventories and the delivery mechanism, a strategic trader may use his future position to corner or squeeze the market, inducing sometimes the bankruptcy of weaker agents. In a more standard approach in industrial organisation, it is shown that a cartel or a dominant producer would find profitable the collapse of the future market when he faces a competitive fringe, if he is able to monopolize storage, suggesting that storage and futures are substitutes. Indeed without futures the fringe is unable to hedge her production, reducing therefore her competition on the market. In that case the competitive fringe is unable to hedge its production. However by essence the consequence of storage or futures is to commit the decisions posterior to these choices: therefore they may be used to obtain endogenously a first mover advantage regarding future competition. Whereas a forward contract has the particularity to reduce the spot market demand, modifying therefore the condition of competition for all agents, storage is a private decision that affects only the agent taking this decision by modifying the cost at which he may sell on the market. Competition between Cournot competitors building inventories may then end-up in an asymmetric issue, when forward sales competition leaves the issue symmetric. Both tools may then be used jointly or not, depending on the return-to-scale.