Certain types of commitments, particularly contractual ones, have been considered anti-competitive practices in the past. The basic idea is that consumers are harmed by forcing them to buy an unwanted good (the linked property) to buy a property they actually want (binding it well) and, therefore, he would prefer that the goods be sold separately. The company that does this pooling can have a significant market share, which allows it to impose the link on consumers despite competitive forces in the market. The tie can also harm other companies in the market for the related property, or that sell only individual components. Loyalty (informal, product-related) is the practice of selling a product or service as a mandatory supplement to the purchase of another product or service. From a legal point of view, a commitment sale subordinates the sale of a property (the link property) to the de facto customer (or de jure customer) to the purchase of a second distinctive commodity (related merchandise). Attachments are often illegal when products are not naturally related. It refers to, but differs from freebie marketing, a common (and legal) method of giving an item (or selling with a substantial discount) to ensure a continuous flow of sales of another related item. Third, a seller must have sufficient market power in a binding product to limit competition in a related product. Market power is measured by the number of buyers the seller has attracted to enter into a specific commitment agreement. Sellers are expanding their market power by encouraging additional buyers to purchase a related product. However, sellers are prohibited from dominating a given market by imprisoning a disproportionate proportion of potential buyers in liaison agreements. Attaching is the “practice of a supplier of a product, the binder, which also requires a buyer to buy a second product, the linked product.”  The commitment of a product can take many forms, contractual commitment when a contract requires the buyer to: Refuse to buy the two products together, refusal of delivery until the buyer agrees to buy both products, withdrawal or withholding of a warranty if the dominant seller only has the benefit of the guarantee when the seller accepts the purchase of that product the technical link occurs when the products of the dominant party are physically integrated and the purchase of one is impossible without the other and when two products are sold in the same package at a price.
These practices are prohibited by Article 101, paragraph 1, point e) and Article 102, paragraph 2, point (d), and may terminate a violation of the statute if other conditions are met. It should be noted, however, that the Court of Justice is prepared to find an offence that goes beyond that of Article 102, paragraph 2, point (d), see Tetra Pak/Commission.  The Section 102 Denser Priority Guidelines set out the circumstances in which measures against fixing practices are appropriate.