dissenting:
Because I continue to believe that M & M Medical Supplies has failed to carry its burden in opposition to the hospital’s motion for summary judgment, I respectfully dissent.
The first element of a claim of monopolization under § 2 of the Sherman Act is “market power.” In order to prove the exercise of market power, a plaintiff must show (1) the existence of some specific, defined geographic market for the product, i.e., the “relevant market,” and (2) the exercise of monopoly power by the defendants in that market. Satellite Television & Associates Resources, Inc. v. Continental Cablevision of Virginia, Inc., 714 F.2d 351 (4th Cir.1983), cert. denied, 465 U.S. 1027, 104 S.Ct. 1285, 79 L.Ed.2d 688 (1984). If the plaintiff fails to prove either of the elements of market power, its entire claim must be dismissed. Consul, Ltd. v. Transco Energy Co., 805 F.2d 490, 495-96 (4th Cir.1986), cert. denied, 481 U.S. 1050, 107 S.Ct. 2182, 95 L.Ed.2d 838 (1987); Satellite Television, 714 F.2d at 357.
In opposition to the motion for summary judgment, M & M submitted an affidavit by Dr. Blair alleging that, based upon his personal investigation and review of the materials produced by Pleasant Valley, the relevant geographic market for durable medical equipment is Mason County, West Virginia. Although Dr. Blair’s affidavit recites the materials he reviewed to reach this conclusion, it fails to cite any of the specific facts that he believes demonstrate that Mason County is the relevant geographic market for durable medical equipment.
As the majority states, several cases have recently held that the proper remedy for an expert’s affidavit that fails to dis-closé the facts supporting its conclusion is supplementation rather than exclusion. See Ambrosini v. Labarraque, 966 F.2d 1464 (D.C.Cir.1992); Monks v. General Elec. Co., 919 F.2d 1189 (6th Cir.1990); Bulthuis v. Rexall Corp., 789 F.2d 1315 (9th Cir.1985). However, I believe that we should adopt the rule of the Eleventh Circuit: An expert’s affidavit submitted in opposition to a motion for summary judgment must set forth specific facts to support its conclusions. Evers v. General Motors Corp., 770 F.2d 984, 986 (11th Cir.1985); see also Slaughter v. Southern Talc Co., 919 F.2d 304, 307 n. 4 (5th Cir.1990). Therefore, I believe that the district court properly refused to consider a conclusory affidavit that furnished no specific facts in opposition to Pleasant Valley’s motion for summary judgment.
Even if I were to find that the district court erred in excluding Dr. Blair’s affidavit, I would still hold that M & M failed to *170define the relevant market. The relevant geographic market is the area in which the suppliers of durable medical equipment effectively compete and to which their customers could practicably turn for alternative sources of such products. Tampa Electric Co. v. Nashville Coal Co., 365 U.S. 320, 331-32, 81 S.Ct. 623, 630, 5 L.Ed.2d 580 (1961); Morgan, Strand, Wheeler & Biggs v. Radiology, Ltd., 924 F.2d 1484, 1490 (9th Cir.1991). Dr. Blair clearly failed to differentiate the market for hospital services, which is not at issue, from the market for durable medical equipment. For example, Dr. Blair reviewed “the patient origin data for Pleasant Valley Hospital” and determined:
The relevant geographic market for hospital services and durable medical equipment in this case is Mason County, West Virginia. The patient origin data strongly suggest that Mason County residents rely predominantly upon Mason County suppliers for their hospital and medical equipment needs....
See supra at pp. 163-64. If M & M had chosen to assert a “tie-in” claim, i.e., that Pleasant Valley Hospital was using its hospital services market share to force its customers to purchase durable medical equipment from Pleasant Valley Home Medical Equipment, the patient origin data for hospital services would be relevant. However, M & M has not asserted a tie-in claim and, therefore, it was wrong for Dr. Blair to rely upon the patient origin data for hospital services in order to determine the geographic market for durable medical equipment.
Assuming, for the purposes of summary judgment, that Dr. Blair relied solely upon the patient origin data from Pleasant Valley Home Medical Equipment in order to determine the relevant market for durable medical equipment, I would still be troubled. Dr. Blair’s affidavit assumes, without offering any evidence to support his assumption, that the relevant market for durable medical equipment may be defined by the residences of the customers of Pleasant Valley Home Medical Equipment. Of course, the area in which a market participant operates does not define the market itself. Morgan, Strand, Wheeler & Biggs v. Radiology, Ltd., 924 F.2d at 1490 (“[A] company may compete in many markets or in only part of a market. Where it competes does not define the market.”).
Finally, although Dr. Blair concedes that the market for durable medical equipment overlaps into the neighboring Ohio counties, he offers no facts to demonstrate how much overlap exists (in absolute or relative terms). For example, 35% of Pleasant Valley Hospital’s customers are not from Mason County. Assuming arguendo that the market for hospital services may be used to define the market for durable medical equipment, Dr. Blair does not even address why this substantial overlap into neighboring counties does not destroy his theory that Mason County alone is the relevant market.
In short, the plaintiff failed to show the existence of a specific, defined geographic market and, therefore, summary judgment was properly entered against M & M.
M & M’s claim for attempted monopolization also requires that it establish the relevant geographic market that Pleasant Valley is allegedly attempting to monopolize. Because M & M has failed to establish the relevant market this claim also must fail.
I would affirm the district court’s grant of summary judgment. I am authorized to state that Circuit Judge DONALD RUSSELL, Circuit Judge WIDENER, Circuit Judge WILKINSON, and Circuit Judge NIEMEYER join in this opinion.