Patents: Pleading to particulars of objection in invalidity claims - Pfizer v Eli Lilly

In Pfizer v Eli Lilly, Justice Potter delivered an important decision on the extent of the patentee's obligation to plead to Particulars of Objection.

When pharmaceutical company Pfizer filed infringement proceedings over two patents, defendants Eli Lilly, Bayer and GlaxoSmithKline filed counterclaims objecting to the validity of the patents in question. In response. Pfizer filed a bare denial to the counterclaims.

In an earlier decision by Justice Potter, (HC Auckland, CIV 2003-404-452, 21 November 2003) the defendants successfully sought orders that Pfizer file a more explicit statement of defence to their counterclaims.

In that judgment, Justice Potter followed an earlier New Zealand Court of Appeal decision in Ancare New Zealand Limited v Ciba Geigy (1997) 11 PRNZ 398.

That decision requires the patentee to respond by properly pleading to the Particulars of Objection. Justice Potter held that the requirement for the patentee to properly plead was not to be confused with the burden of proof. The patentee was still entitled to stand on its patent and to say to the party claiming invalidity, "you prove your objections and show that it is invalid".

Pfizer did not appeal the 2003 decision and Justice Potter found that it had therefore accepted the principles of pleading set forth in that judgment.

In response to Pfizer's revised answers (filed in May 2004), Justice Potter agreed with the defendants' submissions that Pfizer did not include fully particularised answers to each and every allegation, rather the answers were "evasive, containing bare denials to many of the detailed particulars of objection pleaded by the defendants."

In short, Pfizer's answers did not meet the clear spirit and intent of the earlier judgment and were in many respects "an attempt effectively to circumvent that judgment."

Justice Potter did not accept the suggestion from Pfizer that the burden of proof on the defendants provided a justification for denying the particulars sought.

On the question of 'what must be pleaded to meet the principles stated in the 2003 judgment?' Justice Potter noted that, although the onus of proof was carried by the defendants, the patentee nevertheless must plead to meet the case put forward and to narrow the issues for trial.

She found that Pfizer had "rather overstated the case" in contending that it was being required to reveal its closing argument: "Pfizer is being required to provide specific answers and identify specific documents. Argument in relation to them and to issues of construction can properly be developed at trial."