The plaintiffs in Karasik v. Yahoo Inc., a proposed class action, brought a motion for production of Yahoo’s database of its 16.9 million Canadian users prior to the certification motion.  

This class action stems from cyber attacks in 2013 and 2014 by Federal Secret Service of the Russian Federation against the defendants, Yahoo Inc. and Yahoo! Canada Co.

In coming to his decision, Justice Perell noted the following established principles regarding pre-certification productions:

  1. There is no automatic right to documentary discovery at the certification stage, and a party seeking such discovery must demonstrate the need for it; for the certification motion, which is a procedural motion that does not go to the merits of the action, there is limited production of documents that are shown to be relevant to the issues on certification.
  2. The onus is on the party seeking documents for the certification motion to explain why the requested documents are relevant to the issues of certification, and bald assertions that the documents may be relevant do not suffice.
  3. At the pre-certification stage, proportionality is of a particular concern, and the production of documents must be proportionate to the needs of the certification motion and what is necessary to inform the certification hearing.
  4. In determining whether a document should be produced, a guiding principle is fairness, and a party should not request production of more than it needs for the purposes of the certification motion nor should a party hold back the production needed by his or her opponent to inform the focused purposes of the certification hearing.

Ultimately, Justice Perell held that the Plaintiffs did not met the onus of explaining how access to the database was relevant to the certification motion and, in any event, held that the request was disproportionate in the case at hand.

Karasik v. Yahoo Inc., 2019 ONSC 4670 (CanLII)


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