delivered the opinion of the Court.
Section 2(b) of the Clayton Act, 38 Stat. 730, as amended by the Robinson-Patman Act, 49 Stat. 1526, 15 U. S. C. § 13(b), provides that a defendant may rebut a prima facie showing of illegal price discrimination by establishing that its lower price to any purchaser or purchasers “was made in good faith to meet an equally low price of a competitor.” 1 The United States Court of Appeals for the Seventh Circuit has concluded that the “meeting-competition” defense of §2(b) is available only if the defendant sets its lower price on a customer-by-customer basis and creates the price discrimination by lowering rather than by raising prices. We conclude that § 2(b) is not so inflexible.
HH
From July 1, 1972, through November 30, 1978, petitioner Falls City Industries, Inc., sold beer f.o.b. its Louisville, Ky., brewery to wholesalers throughout Indiana, Kentucky, and 11 other States. Respondent Vaneo Beverage, Inc., was the sole wholesale distributor of Falls City beer in Vanderburgh County, Ind. That county includes the city of Evansville. Directly across the state line from Vanderburgh County is Henderson County, Ky., where Falls City’s only wholesale distributor was Dawson Springs, Inc. The city of Henderson, Ky., located in Henderson County, is less than 10 miles from Evansville. The two cities are connected by a four-lane interstate highway. The two counties generally are considered to be a single metropolitan area. App. 124.
*432 Vaneo and Dawson Springs each purchased beer from Falls City and other brewers and resold it to retailers in Van-derburgh County and Henderson County, respectively. The two distributors did not compete for sales to the same retailers. This was because Indiana wholesalers were prohibited by state law from selling to out-of-state retailers, Ind. Code §7.1-3-3-5 (1982), and Indiana retailers were not permitted to purchase beer from out-of-state wholesalers. See §7.1-3-4-6. Indiana law also affected beer sales in two other ways relevant to this case. First, Indiana required brewers to sell to all Indiana wholesalers at a single price. §7.1-5-5-7. Second, although it was ignored and virtually unenforced, see Tr. 122-123, 135-136, state law prohibited consumers from importing alcoholic beverages without a permit. § 7.1-5-11-1.
In December 1976, Vaneo sued Falls City in the United States District Court for the Southern District of Indiana, alleging, among other things, that Falls City had discriminated in price against Vaneo, in violation of §2(a) of the Clayton Act, 38 Stat. 730, as amended by the Robinson-Patman Act, 49 Stat. 1526, 15 U. S. C. § 13(a), 2 by charging Vaneo a higher price than it charged Dawson Springs. Vaneo also claimed that Falls City had violated §§ 1 and 2 of the Sherman Act, 15 U. S. C. §§ 1 and 2, by conspiring with other brewers and unnamed wholesalers to maintain higher prices in Indiana than in Kentucky.
After trial, the District Court dismissed Vanco’s Sherman Act claims, finding no evidence to support the allegations of
*433
conspiracy or monopolization.
*432 “It shall be unlawful for any person engaged in commerce, in the course of such commerce, either directly or indirectly, to discriminate in price between different purchasers of commodities of like grade and quality, where either or any of the purchases involved in such discrimination are in commerce ... and where the effect of such discrimination may be substantially to lessen competition or tend to create a monopoly in any line of commerce, or to injure, destroy, or prevent competition with any person who either grants or knowingly receives the benefit of such discrimination, or with customers of either of them . . .
*434 The District Court rejected Falls City’s § 2(b) meeting-competition defense. The court reasoned that, instead of reducing its prices to meet those of a competitor, Falls City had created the price disparity by raising its prices to Indiana wholesalers more than it had raised its Kentucky prices. Instead of “adjusting prices on a customer to customer basis to meet competition from other brewers,” id., at 75,822, Falls City charged a single price throughout each State in which it sold beer. The court concluded that Falls City’s higher Indiana price was not set in good faith; instead, it was raised “for the sole reason that it followed the other brewers ... for its profit.” Ibid.
The United States Court of Appeals for the Seventh Circuit, by a divided vote, affirmed the finding of liability.
HH HH
To establish a prima facie violation of § 2(a), one of the elements a plaintiff must show is a reasonable possibility that a
*435
price difference may harm competition.
Corn Products Refining Co.
v.
FTC,
Palls City contends that the Court of Appeals erred in relying on FTC v.
Morton Salt Co.,
*436
According to Falls City, the
Morton Salt
rule should be applied only in cases involving “large buyer preference or seller predation.” Brief for Petitioner 31. Falls City does not, however, suggest any economic reason why
Morton
Saifs “self-evident” inference,
The Morton Salt rule was not misapplied in this case. In a strictly literal sense, this case differs from Morton Salt because Vaneo and Dawson Springs did not compete with each other at the wholesale level; Vaneo sold only to Indiana retailers and Dawson Springs sold only to Kentucky retailers. But the competitive injury component of a Robinson-Patman Act violation is not limited to the injury to competition between the favored and the disfavored purchaser; it also encompasses the injury to competition between their customers — in this case the competition between Kentucky retailers and Indiana retailers who, under a District Court finding not challenged in this Court, were selling in a single, interstate retail market. 7
*437
After observing that Falls City had maintained a substantial price difference between Vaneo and Dawson Springs over a significant period of time, the Court of Appeals, like the District Court, considered the evidence that Vanco’s loss of Falls City beer sales was attributable to factors other than the price difference, particularly the marketwide decline of Falls City beer. Both courts found it likely that this overall decline accounted for some — or even most — of Vanco’s lost sales. Nevertheless, if some of Vanco’s injury was attributable to the price discrimination, Falls City is responsible to that extent. See
Perma Life Mufflers, Inc.
v.
International Parts Corp.,
The Court of Appeals agreed with the District Court’s findings that “the major reason for the higher Indiana retail beer prices was the higher prices charged Indiana distributors,” and “the lower retail prices in Henderson County attracted Indiana customers away from Indiana retailers, thereby causing the retailers to curtail purchases from Vaneo.”
hH I — I HH
When proved, the meeting-competition defense of § 2(b) exonerates a seller from Robinson-Patman Act liability.
Standard Oil Co.
v.
FTC,
Instead, the Court of Appeals reasoned that Falls City had otherwise failed to show that its pricing “was a good faith effort” to meet competition.
A
On its face, §2(b) requires more than a showing of facts that would have led a reasonable person to believe that a lower price was available to the favored purchaser from a competitor. The showing required is that the “lower price . . . was made in good faith to meet” the competitor’s low price. 15 U. S. C. § 13(b) (emphasis added). Thus, the defense requires that the seller offer the lower price in good faith for the purpose of meeting the competitor’s price, that is, the lower price must actually have been a good-faith response to that competing low price. See Rowe, at 234-235. See generally Kuenzel & Schiffres, Making Sense of Robinson-Patman: The Need to Revitalize Its Affirmative Defenses, 62 Va. L. Rev. 1211, 1237-1255 (1976). In most situations, a showing of facts giving rise to a reasonable belief that equally low prices were available to the favored purchaser from a competitor will be sufficient to establish that the seller’s lower price was offered in good faith to meet that price. In others, however, despite the availability from other sellers of a low price, it may be apparent that the defendant’s low offer was not a good-faith response.
*440
In
Staley,
this Court applied that principle. The Federal Trade Commission (FTC) had proceeded against Staley and six competing manufacturers of glucose, all of whom adhered to the same Chicago basing-point pricing system. See C. Edwards, Price Discrimination Law 372-379 (1959). See generally FTC Policy Toward Geographic Pricing Practices, 1 CCH Trade Reg. Rep. ¶¶3601.27, 3601.40-3601.42, pp. 5346, 5351-5352 (10th ed. 1959). Like its competitors, Staley, whose plant was located in Decatur, Ill., sold glucose to candy and syrup manufacturers at a delivered price that included the freight rate from Chicago to the point of delivery. Purchasers nearer Decatur thus were charged an element of “phantom” freight, while Staley “absorbed” an element of freight in sales to buyers nearer Chicago.
The FTC eventually charged all seven manufacturers individually with price discrimination and jointly under the Federal Trade Commission Act with price fixing. See
Corn Products Refining Co.,
47 F. T. C. 587 (1950). At the time of the
Staley
decision, both the FTC and this Court had determined that use of the pricing system by Staley’s competitors was illegal under §2(a). See
Com Products Refining Co.
v.
FTC,
The Court observed that § 2(b) could exonerate Staley only if that section permitted a seller to establish “an otherwise unlawful system of discriminatory prices” in order to benefit from “a like unlawful system maintained by his competitors.”
*441
Thus, even had Staley been able to show that its prices throughout the country did not undercut those of its competitors, its lower price in the Chicago area was not a good-faith response to the lower prices there. Staley had not priced in response to competitors’ discrete pricing decisions, but from the outset had followed an industrywide practice of setting its prices according to a single, arbitrary scheme that by its nature precluded independent pricing in response to normal competitive forces.
B
Almost 20 years ago, the FTC set forth the standard that governs the requirement of a “good-faith response”:
“At the heart of Section 2(b) is the concept of ‘good faith’. This is a flexible and pragmatic, not a technical or doctrinaire, concept. The standard of good faith is simply the standard of the prudent businessman responding fairly to what he reasonably believes is a situation of competitive necessity.” Continental Baking Co., 63 F. T. C. 2071, 2163 (1963).
Whether this standard is met depends on “ ‘the facts and circumstances of the particular case, not abstract theories or remote conjectures.’ ”
United States
v.
United States Gypsum Co.,
*442 The “facts and circumstances” present in Staley differ markedly from those present here. Although the District Court characterized the Indiana prices charged by Falls City and its competitors as “artificially high,” there is no evidence that Falls City’s lower prices in Kentucky were set as part of a plan to obtain artificially high profits in Indiana rather than in response to competitive conditions in Kentucky. Falls City did not adopt an illegal system of prices maintained by its competitors. 9 The District Court found that Falls City’s prices rose in Indiana in response to competitors’ price increases there; it did not address the crucial question whether Falls City’s Kentucky prices remained lower in response to competitors’ prices in that State.
Vaneo attempts to liken this case to
Staley
by arguing that the existence of industrywide price discrimination within the single geographic retail market itself indicates “tacit or explicit collusion, or . . . market power” inconsistent with a good-faith response. Brief for Respondent 39. By its terms, however, the meeting-competition defense requires a seller to justify only its
lower
price. See
Staley,
*443 Moreover, the collusion argument founders on a complete lack of proof. Persistent, industrywide price discrimination within a geographic market should certainly alert a court to a substantial possibility of collusion. 10 See Posner, Oligopoly and the Antitrust Laws: A Suggested Approach, 21 Stan. L. Rev. 1562, 1578-1579 (1969). Here, however, the persistent interstate price difference could well have been attributable, not to Falls City, but to extensive state regulation of the sale of beer. Indiana required each brewer to charge a single price for its beer throughout the State, and barred direct competition between Indiana and Kentucky distributors for sales to retailers. In these unusual circumstances, the prices charged to Vaneo and other wholesalers in Vander-burgh County may have been influenced more by market conditions in distant Gary and Fort Wayne than by conditions in nearby Henderson County, Ky. Moreover, wholesalers in Henderson County competed directly, and attempted to price competitively, with wholesalers in neighboring Kentucky counties. App. 52-53. A separate pricing structure might well have evolved in the two States without collusion, not *444 withstanding the existence of a common retail market along the border. Thus, the sustained price discrimination does not itself demonstrate that Falls City’s Kentucky prices were not a good-faith response to competitors’ prices there.
C
The Court of Appeals explicitly relied on two other factors in rejecting Falls City’s meeting-competition defense: the price discrimination was created by raising rather than lowering prices, and Falls City raised its prices in order to increase its profits. Neither of these factors is controlling. Nothing in § 2(b) requires a seller to lower its price in order to meet competition. On the contrary, § 2(b) requires the defendant to show only that its “lower price . . . was made in good faith to meet an equally low price of a competitor.” A seller is required to justify a price difference by showing that it reasonably believed that an equally low price was available to the purchaser and that it offered the lower price for that reason; the seller is not required to show that the difference resulted from subtraction rather than addition.
A different rule would not only be contrary to the language of the statute, but also might stifle the only kind of legitimate price competition reasonably available in particular industries. In a period of generally rising prices, vigorous price competition for a particular customer or customers may take the form of smaller price increases rather than price cuts. Thus, a price discrimination created by selective price increases can result from a good-faith effort to meet a competitor’s low price.
Nor is the good faith with which the lower price is offered impugned if the prices raised, like those kept lower, respond to competitors’ prices and are set with the goal of increasing the seller’s profits. A seller need not choose between “ruinously cutting its prices to all its customers to match the price offered to one, [and] refusing to meet the competition and
*445
then ruinously raising its prices to its remaining customers to cover increased unit costs.”
Standard Oil Co.
v.
FTC,
Section 2(b) does not require a seller, meeting in good faith a competitor’s lower price to certain customers, to forgo the profits that otherwise would be available in sales to its remaining customers. The very purpose of the defense is to permit a seller to treat different competitive situations differently. The prudent businessman responding fairly to what he believes in good faith is a situation of competitive necessity might well raise his prices to some customers to increase his profits, while meeting competitors’ prices by keeping his prices to other customers low.
The Court in
Staley
said that the meeting-competition defense “presupposes that the person charged with violating the Act would, by his normal, non-discriminatory pricing methods, have reached a price so high that he could reduce it in order to meet the competitor’s equally low price.”
D
Vaneo also contends that Falls City did not satisfy § 2(b) because its price discrimination “was not a
defensive
response to competition.” Brief for Respondent 47 (emphasis supplied). According to Vaneo, the Robinson-Patman Act permits price discrimination only if its purpose is to retain a customer.
Id.,
at 32-33. We agree that a seller’s response must be defensive, in the sense that the lower price must be calculated and offered in good faith to “meet not beat” the competitor’s low price. See
United States Gypsum Co.,
<1
The Court of Appeals also relied on
Staley
for the proposition that the meeting-competition defense “ ‘places emphasis on individual [competitive] situations, rather than upon a general system of competition,”’
*448
There is no evidence that Congress intended to limit the availability of § 2(b) to customer-specific responses. Section 2(b)’s predecessor, § 2 of the original Clayton Act, stated that “nothing herein contained shall prevent. . . discrimination in price in the same or different communities made in good faith to meet competition.” 38 Stat. 730. The Judiciary Committee of the House of Representatives, which drafted the clause that became the current § 2(b), see
Standard Oil Co.
v.
FTC,
Section 2(b) specifically allows a “lower price ... to any purchaser or purchasers” made in good faith to meet a competitor’s equally low price. A single low price surely may be extended to numerous purchasers if the seller has a reasonable basis for believing that the competitor’s lower price is available to them. 15 Beyond the requirement that the lower *449 price be reasonably calculated to “meet not beat” the competition, Congress intended to leave it a “question of fact . . . whether the way in which the competition was met lies within the latitude allowed.” 80 Cong. Rec. 9418 (1936) (remarks of Rep. Utterback). Once again, this inquiry is guided by the standard of the prudent businessman responding fairly to what he reasonably believes are the competitive necessities.
A seller may have good reason to believe that a competitor or competitors are charging lower prices throughout a particular region. See
William Inglis & Sons Baking Co.
v.
ITT Continental Baking Co.,
In
Staley,
Of course, a seller must limit its lower price to that group of customers reasonably believed to have the lower price available to it from competitors. A response that is not reasonably tailored to the competitive situation as known to the seller, or one that is based on inadequate verification, would not meet the standard of good faith. Similarly, the response may continue only as long as the competitive circumstances justifying it, as reasonably known by the seller, persist.
17
One choosing to price on a territorial basis, rather than on a
*451
customer-by-customer basis, must show that this decision was a genuine, reasonable response to prevailing competitive circumstances. See
International Air Industries, Inc.
v.
American Excelsior Co.,
V
In summary, the meeting-competition defense requires the seller at least to show the existence of facts that would lead a reasonable and prudent person to believe that the seller’s lower price would meet the equally low price of a competitor; it also requires the seller to demonstrate that its lower price was a good-faith response to a competitor’s lower price.
Falls City contends that it has established its meeting-competition defense as a matter of law. In the absence of further findings, we do not agree. The District Court and the Court of Appeals did not decide whether Falls City had shown facts that would have led a reasonable and prudent person to conclude that its lower price would meet the equally low price of its competitors in Kentucky throughout the period at issue in this suit. Nor did they apply the proper standards to the question whether Falls City’s decision to set a single statewide price in Kentucky was a good-faith, well-tailored response to the competitive circumstances prevailing there. The absence of allegations to the contrary is not controlling; the statute places the burden of establishing the defense on Falls City, not Vaneo. There is evidence *452 in the record that might support an inference that these requirements were met, 18 but whether to draw that inference is a question for the trier of fact, not this Court.
Accordingly, the judgment of the Court of Appeals is vacated, and the case is remanded for further proceedings consistent with this opinion.
It is so ordered.
Notes
Section 2(b)’s “meeting-competition” proviso reads:
“[N]othing herein contained shall prevent a seller rebutting the prima-facie case thus made by showing that his lower price or the furnishing of services or facilities to any purchaser or purchasers was made in good faith to meet an equally low price of a competitor, or the services or facilities furnished by a competitor.”
That section provides in relevant part:
Palls City charged Vaneo and other Indiana distributors 10-30% more than it charged Dawson Springs and other Kentucky distributors. The District Court concluded that this price differential was not explained by differing costs. Falls City’s distributors — wherever located — picked up the beer at Falls City’s Louisville brewery. 1980-2 Trade Cases, at 75,814.
The District Court acknowledged that during the period at issue, sales of Falls City beer dropped precipitously throughout Indiana and Kentucky. Id., at 75,815. This decline paralleled a significant nationwide trend that favored national brands of beer and harmed or eliminated many regional brewers like Falls City. See generally, FTC, Staff Report of Bureau of Economics, The Brewing Industry 13-28 (1978). But Vanco’s sales of Falls City beer declined more rapidly than did Falls City’s sales in Indiana *434 as a whole, or in Henderson County. Moreover, Falls City’s rate of decline in Henderson County was less than that in Kentucky as a whole. The District Court found that the difference between Vanco’s rate of decline and the rate of decline elsewhere was caused by Falls City’s price discrimination. 1980-2 Trade Cases, at 75,815.
The Court of Appeals remanded the case to the District Court for a re-determination of damages because, contrary to our decision in
J. Truett Payne Co.
v.
Chrysler Motors Corp.,
Section 4 of the Clayton Act requires “some showing of actual injury attributable to something the antitrust laws were designed to prevent.”
J. Truett Payne Co.
v.
Chrysler Motors Corp.,
The Court of Appeals upheld the District Court’s findings that the sale of Falls City beer to Vaneo was in interstate commerce and that Henderson County and Vanderburgh County constituted a unified retail market for beer. Id., at 1227-1229. These holdings are not before us. Falls City does not argue, and never has argued, that “Indiana’s consumer-level non- *437 importation law compels a finding that Evansville and Henderson are separate retail beer markets.” Reply Brief for Petitioner to Supplemental Brief after Oral Argument 3. Indeed, Falls City’s counsel affirmatively waived this argument in a letter written to the District Court before trial, App. to Supplemental Brief for Respondent after Oral Argument. Nor is the broader question whether Indiana and Kentucky constitute separate markets fairly included within the scope of the questions presented in Falls City’s petition for certiorari. Counsel for Falls City made this very clear at oral argument, stating that “I’m not asking this Court to delve into the record to second guess that determination by the lower courts.” Tr. of Oral Arg. 5-6.
Falls City’s own sales agent reported that the different prices charged in the two States accounted — at least in part — for the substantial difference in Vanco’s and Dawson Spring’s sales performances. App. 97-98, 157, 166. The local press reported substantial purchases of beer in Kentucky by Indiana residents. Tr. 114-122,128. Kentucky retailers located just south of the Indiana state line on the four-lane highway between *438 Evansville and Henderson advertised their low prices extensively in the Evansville media and utilized “drive-in windows” at which customers could purchase beer without leaving their cars. E. g., id., at 336. Witnesses testified that they observed cars with Indiana license plates parked at Henderson County carryout retailers, to which drivers would return carrying cases of beer. Id., at 86-112, 629-632. One Indiana resident testified that he purchased beer in Kentucky because of lower prices there. Id., at 121-122, 218-222, 229. The District Court also relied on the differing rates of decline. See n. 4, supra.
Except through its rejected Sherman Act claim, Vaneo has never attempted to prove that the competing prices Falls City claims to have met were themselves illegal, or that Falls City met those prices knowing them to be unlawful. The plaintiff bears the burden of proving that the prices met were actually illegal.
Cadigan
v.
Texaco, Inc.,
Indeed, in some circumstances there may be no other plausible explanation for persistent “economic” price discrimination. Cf.
FTC
v.
Cement Institute,
“Economic” price discrimination consists in selling a product to different customers at prices that bear different ratios to the marginal costs of sales to those customers, for example, charging the same price to two customers despite the fact that the seller incurs higher costs to serve one than the other, or charging different prices to two customers despite the fact that the seller’s costs of service are the same. Price discrimination under the Robinson-Patman Act, however, “is merely a price difference.”
FTC
v.
Anheuser-Busch, Inc.,
“Section 2(b) should not require proof that the seller departed from a previously uniform price schedule. Such previous pricing is not relevant to evaluation of genuine responses to a current competitive situation.” Report of the Attorney General’s National Committee to Study the Antitrust Laws 182 (1955) (1955 Report) (emphasis in original).
At least three Courts of Appeals have held that the defense is not limited to attempts to retain customers.
Cadigan
v.
Texaco, Inc.,
Standard Oil Co.
v.
FTC,
Compare
Exquisite Form Brassiere, Inc.
v.
FTC,
123 U. S. App. D. C. 358, 359,
See also
Standard Oil Co.
v.
FTC,
See Rowe, at 240 (“a seller’s area-wide and blanket lower price, if made in good faith to meet competitors’ lower prices, may be justified ... as responsive to an ‘individual competitive situation’ ”). Cf.
Maryland Baking Co.
v.
FTC,
See Klein, Meeting Competition by Price Systems Under § 2(b) of the Robinson-Patman Act: Problems and Prospects, 16 Antitrust Bull. 213, 233-234, 238 (1971); Kuenzel & Schiffres,
Were the courts below to find that Falls City reasonably believed that low prices were available to Dawson Springs and other Kentucky wholesalers from Falls City’s competitors, a factfinding that we decline to address on this record, Falls City could not easily have eliminated price discrimination between Dawson Springs and Vaneo. In such circumstances, had Falls City raised prices in Kentucky in lockstep with price increases in Indiana, it would have lost sales in Kentucky because its competitors would have been offering far lower prices. Raising its Kentucky prices only in Henderson County would not only have cost Falls City sales there, but also might have exposed Falls City to new Robinson-Patman Act claims, since Dawson Springs competed for sales with wholesalers in neighboring Kentucky counties. Nor, in such circumstances, could Falls City reasonably be required to charge Vaneo the lower Kentucky price. Indiana law prohibited Falls City from doing so without simultaneously offering the same price to all other Indiana wholesalers. This approach might well have harmed Falls City’s economic interests, since most of Falls City’s Indiana sales were in areas far removed from lower Kentucky prices and competition.
