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Case Law Alert: Court Rules Party Must Validate Their Production Efforts

Created on December 28, 2018

Director of Marketing Programs at Exterro

In City of Rockford v. Mallinckrodt ARD Inc. (N.D. Ill. Aug. 7, 2018), the ruling demonstrated that when it comes to validating your production efforts, sampling your null set may be necessary to prove that a reasonable inquiry was taken by the producing party.


In this breach of contract case involving pricing for prescription medication, the parties dispute an element of their e-discovery production protocol, namely what happens after production if one party feels “certain categories of requested documents exist that were not included in production.”

The plaintiffs proposed that a random sample be taken of the null set (i.e., the “set of documents that are not returned as responsive by a search process, or that are identified as not relevant by a review process”), while the defendants believed that the parties should “meet and confer to discuss whether additional terms are necessary.”

Leading up to this dispute, the parties agreed to use keyword searching, but if one party decides to use predictive coding, “the producing party will notify the opposing party to discuss the protocol for that type of review.”


  • Court sides with the plaintiff. The court ordered the defendant to sample their null set with keyword or predictive coding technology. By doing this, it will allow the court to know if a “reasonably inquiry” was conducted under FRCP 26(g)(1).
  • It’s proportionate to sample the null set. When weighing proportionality in making its ruling, the court deemed that sampling a null set would not be “unreasonably expensive or burdensome.” The defendant failed to provide any evidence that sampling the null set was disproportionate.
  • Court commends parties’ cooperation. The court was impressed with the parties’ level of cooperation especially in a “classic asymmetrical discovery” case stating, “The litigation so far is a solid example that zealous advocacy is not necessarily incompatible with cooperation. The current issue before the Court is an example of that advocacy and cooperation.”

Expert Analysis from Cristin K. Traylor, Esq., Counsel, McGuireWoods

Although sampling the null set is not required, it is one method to show that the search terms were valid when a party is looking for additional assurances that the process yielded reasonable results.

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