【判例】均等論

在申請專利範圍修正時，若因不能加入均等物而被拒絕，並不會構成放棄均等論的推定，可以參見「Smithkline Beecham Corp. (DBA GlaxoSmithKline) v. Excel Pharmaceuticals, Inc. et al. 」案。

為了某些原因（To avoid the need for multiple dosages with the attendant fluctuations in plasma bupropion concentrations）， Glaxo發明了具持續釋放型的化學物質。並獲得了專利以保護它持續釋放型的藥物（sustained release formulation of the drug），在其專利的申請專利範圍要求了，包含bupropion hydrochloride and HPMC混合物的緩釋片（sustained release tablet）。但原始申請專利範圍並沒有包含HPMC，而被the examiner rejected the claims that did not recite HPMC而沒有滿足實施可能的要件 （for lack of enablement under 35 U.S.C. § 112, 1）。所以Glaxo修正claim增加HPMC於claim中克服了拒絕理由而獲得專利。而被控一方則：The sustained release agent in Excel’s generic composition is polyvinyl alcohol (PVA), a hydrogel-forming polymer。因此Glaxo對Excel興起訴訟。

在district court訴訟過程中：During litigation, Excel moved for summary judgment of noninfringement because its formulation does not contain HPMC. Excel contended that prosecution history estoppel precludes infringement under the doctrine of equivalents.。
結果：The district court concluded: “[T]his amendment was made to satisfy the requirements of 35 U.S.C. § 112, and, therefore, the amendment was ‘made for a reason related to patentability.’

Glaxo上訴，最後的判決的結論是：However, the present record does not address the foreseeability of PVA at the time of the narrowing amendment. Thus, this record does not address whether Glaxo has rebutted the presumption of surrendered equivalents. 「Upon remand, the trial court may address whether PVA constitutes a foreseeable sustained release agent or an unforeseeable technology. 」 Because a material issue of fact remains to be resolved, Excel was not entitled to summary judgment of noninfringement as a matter of law.

一、此件的爭點在於“預見的可能性”，CAFC對“預見的可能性”做了較窄的解譯。
二、過程中因為不能追加新事項並不能當作“反駁均等物推定的反證”。另外，關於此因新事項而無法增加PVA當作申請專利範圍，應該於事後再提CIP加入，才能擴大保護範因。