An Oregon federal judge denied Kroger and Albertsons' requests for more information on the markets at issue in the Federal Trade Commission's ongoing attempt to block their merger, saying the companies' request is premature and excessively broad.

In a motion to compel in May, the supermarket chains jointly requested the underlying basis for the FTC's market share and concentration figures — including the Herfindahl-Hirschman Index (HHI), a measure for market competition and concentration, and boundaries for each geographic market the FTC is claiming would be harmed by the merger.

But on Friday, U.S. District Judge Adrienne Nelson said some of the interrogatories were more appropriate for the expert discovery phase while others were simply too broad and would require too much attorney work product for her to grant.

"Market share calculations and methodologies constitute legal conclusions and are likely to provide insight into the mental impressions of attorneys," Judge Nelson said Friday. "The market shares themselves, as well as any HHI calculations, are the product of legal and economic analyses performed by counsel to the United States … in preparation for this litigation. Such analyses are precisely the type of 'conclusions' which Rule 26(b)(3)(B) prohibits a court from ordering disclosed."

As for the bases and methodologies used for the FTC complaint's market analysis, Judge Nelson said those requests should be "reserved for the expert discovery period," as they necessarily require applications of antitrust law to facts.

In another request, the companies seek "all facts, documents, and data" pertaining to the FTC's definition of market competitors, its economic and legal analysis, and claims that the merger would be anti-competitive for workers. Judge Nelson called those interrogatories "excessively broad."

In the Herfindahl-Hirschman Index, markets that score 1500 or lower are typically considered competitive while markets that score above 2500 are generally thought to be highly concentrated. According to the FTC's February complaint, the merger — between the country's two largest traditional supermarket chains — would increase the HHI in over 100 local markets by more than 100 points. In each of the markets, the commission claims, the new supermarket chain would have a combined market share of more than 30%, or a post-merger HHI of more than 1800.

The result, the FTC argues, would be a supermarket chain so big and with so much market share it would be "presumptively unlawful" under antitrust law.

"The proposed acquisition would eliminate substantial head-to-head competition between defendants in the communities in which both firms operate supermarkets today," the FTC argues in its complaint.

But in their motion to compel the government's response to their interrogatories, Kroger Co. and Albertsons Cos. Inc. say the specific "contours" of relevant markets will be key to the litigation, adding that the FTC was ignoring how the growth of other competitors like Costco Wholesale Corp., Aldi, and online shopping platforms have changed how shoppers get their groceries.

"Without basic facts stating who plaintiffs allege is in or out of the market and how big those markets allegedly are, defendants cannot even understand, much less adequately defend themselves, against the allegations in the complaint," the companies argue in their filing last month.

According to a briefing schedule agreed to in March, the government will file an opening brief in support of a preliminary injunction to block the merger by July 24. Kroger and Albertsons will have until Aug. 9 to reply.

None of the parties immediately responded to Law360's requests for comment Monday.

The FTC is represented in-house by James H. Weingarten, Charles Dickinson, Rohan Pai, Laura R. Hall, Elizabeth Arens, Jeanine Balbach, Katherine Bies, Emily Blackburn, Katherine Drummonds, Paul Frangie, Jacob Hamburger, Lily Hough, Janet Kim, Kenneth A. Libby, Eric Olson, Harris Rothman, Joshua Smith and Albert Teng.

Albertsons is represented by James A. Fishkin and Michael G. Cowie of Dechert LLP, and Edward D. Hassi, Michael Schaper, Shannon Rose Selden, J. Robert Abraham and Natascha Born of Debevoise & Plimpton LLP.

Kroger is represented by Matthew M. Wolf, Michael B. Bernstein, Jason C. Ewart, Joshua M. Davis, Matthew M. Shultz, Yasmine Harik and John Holler of Arnold & Porter Kaye Scholer LLP, and Mark A. Perry, Luna Barrington and Luke Sullivan of Weil Gotshal & Manges LLP.