The Quickie brand wheelchair is the most popular customized wheelchair on the market. Its market share is 90 percent. Other manufacturers produce special-use wheelchairs that fold, that are made of mesh with light frames, and that are easily transportable. These manufacturers do not compete with Quickie on customized chairs. One manufacturer states: “Look, it’s an expensive market to be in, that Quickie market. We prefer the alternative chairs without the headache of customization.” Another adds: “It is such a drain on flow in the market because insurance companies take so long to pay. We produce chairs that buyers purchase with their own money, not through insurers. Our sales are just like any other product.” Quickie entered the market nearly 40 years ago and is known for its quality and attention to detail. Buying a Quickie custom chair, however, takes time and the revenue stream from the sales is slow but steady because of the time required to produce custom chairs. Has Quickie violated the federal antitrust laws with its 90 percent market share?