The State of Kentucky sued Marathon Petroleum and related parties for violating antitrust laws. Kentucky claimed that Marathon’s anticompetitive practices caused consumers to be overcharged.

Marathon asked the court to exclude the testimony of Kentucky’s expert economist. The court granted that motion and, since Kentucky could not prevail without the expert’s testimony, dismissed the case.

Antitrust Arguments

Marathon owns the largest refineries in the Midwest and the only refinery in Kentucky. It is also the largest supplier of gasoline in Northern Kentucky.

Kentucky argued that Marathon monopolized the wholesale market for Summer RFG, a kind of gasoline that some Kentucky retailers are required to sell during the summer months. A necessary ingredient of RFG is a petroleum product abbreviated as RBOB. Wholesalers purchase RBOB and add ethanol and other products to create RFG. They then sell the RFG from their terminals to retailers.

Kentucky argued that Marathon controls the influx of RBOB and thus monopolizes the downstream market for RFG. Kentucky alleged that Marathon used its market share dominance to manipulate the wholesale and retail price of gasoline. That price, according to Kentucky, was higher than the prices that prevail in competitive markets. Kentucky also alleged that Marathon uses anticompetitive supply agreements (known as exchange agreements) to maintain its market dominance.

Expert Testimony in Antitrust Cases

When a plaintiff alleges that a defendant has restrained trade or engaged in monopolistic pricing within a market, the plaintiff’s first task is to define that market.

The plaintiff must define a product market and a geographic market. The product market analysis asks whether there are readily available interchangeable substitute goods that consumers could purchase to serve their needs. A substitute is interchangeable if an increase in price for one product would cause an increase in demand for the substitute product.

A geographic market is the area in which sellers compete against each other to make sales to the same consumers. In simple terms, it is the market area in which the allegedly anticompetitive seller operates.

The relevant market is a fact question that must generally be determined by a jury. A judge’s disagreement with the plaintiff about the relevant market should not lead to a dismissal of the case unless no reasonable juror could agree with the plaintiff’s definition.

Courts usually require the relevant market to be proved by an expert opinion based on sound principles of economics. While a judge cannot dismiss a case simply because the judge disagrees with the expert’s view of the facts, a judge can exclude the expert’s testimony if the judge finds that the testimony is not based on a reliable methodology.

Kentucky relied on a single expert witness, Dr. Michael Sattinger. Marathon did not challenge Sattinger’s qualifications to render an expert opinion. Rather, it challenged the methodology he used to determine the relevant market, to determine the existence of an antitrust injury, and to calculate damages.

Relevant Market

Sattinger defined the relevant geographic market as the Kentucky terminals where RBOB is blended with other products and sold to retailers as RFG. The court decided that Sattinger failed to base that definition on a reliable methodology.

Economists usually use a “hypothetical monopolist” or “small but significant and non-transitory increase in price” (SSNIP) test to determine the relevant market. That test asks whether consumers would leave a market for competing goods if a supplier were to impose a 5{d61575bddc780c1d4ab39ab904bf25755f3b8d1434703a303cf443ba00f43fa4} price increase for at least one year. If consumers would not leave the market, the market is worth monopolizing. The smallest market from which consumers would not exit is the relevant market.

Courts have generally agreed that the SSNIP test is a reasonable methodology for defining a relevant market. Sattinger acknowledged that the SSNIP test is widely used but chose not to use it. The court noted that economists are not required to use the SSNIP test to define a relevant market, but are required to use some other reasonable methodology. The court faulted Sattinger for failing to explain why he limited the relevant market to terminals in Kentucky.

The court also concluded that defining Kentucky terminals as the relevant market did not reflect the economic realities of the wholesale RFG market. The court thought Sattinger should have asked whether there were other places wholesalers could look to buy RBOB. The court noted that Marathon’s only local competitor had RBOB transported by barge from other states, and that Marathon itself had met its need for RBOB by transporting it to Kentucky by truck.

Since Sattinger did not define a geographic market that included all reasonably available sources of RBOB, Sattinger did not base his opinion on a reasonable methodology. According, his opinion was inadmissible.

Antitrust Injury

To demonstrate that Marathon’s anticompetitive behavior caused a harm, Sattinger compared markets for RFG in Baltimore and St. Louis to the Kentucky market. He determined that market prices were lower in those cities and attributed the price differential to Marathon’s anticompetitive behavior. He calculated the price difference over the time period covered by the lawsuit and produced a damages calculation of about $173 million.

While the court recognized that Sattinger’s “yardstick method” of damages calculation can be appropriate in antitrust cases, the method must take account of other factors (such as market size, product demand, proximity to supply sources, and cost of operations) that might have an independent impact on prices. Economists generally use a regression analysis to account for those variables, but Sattinger failed to rule out other possible explanations for price differences that were unrelated to Marathon’s anticompetitive pricing.

Kentucky also considered Marathon’s use of exchange agreements to be anticompetitive. Competing refiners use exchange agreements to trade gasoline when a competitor has an insufficient supply. Sattinger did not determine whether exchange agreements are used in Baltimore or St. Louis and therefore failed to determine whether the supposedly anticompetitive agreements had an impact on price.

The court ultimately concluded that Sattinger’s methodology did not rest on sound economic principles. Accordingly, his opinions did not satisfy Daubert and were not admissible as evidence.

Lessons Learned

Different judges view Daubert in different ways, but precedent authored by some appellate judges supported the exclusion of Sattinger’s testimony. Part of case preparation should include a thorough review of Daubert precedent in the case at hand. In this case, a review of Daubert decisions in antitrust cases might have prepared Kentucky’s lawyers for Marathon’s challenges.

Experts should be urged to complete a first draft of a report for an attorney’s review well in advance of the disclosure deadline. If Kentucky’s lawyers had identified attacks that could be made on their expert’s methodology, perhaps those perceived flaws could have been corrected before a final draft was prepared.

Experts understand their field of expertise but lawyers understand precedent. Helping experts understand how a court might respond to Daubert challenges is a key role that lawyers must play after they hire expert witnesses.