In September 2014, the Supreme Court of Appeal of South Africa (Supreme Court) issued a decision in Pharma Dynamics (Proprietary) Limited (Pharma) versus Bayer Pharma AG (formerly Bayer Schering Pharma AG) andBayer (Proprietary) Limited (Bayer Pharma AG and Bayer Limited will be collectively referred to as “Bayer”) relating to Bayer’s South African Patent No. 2004/4083 entitled “Pharmaceutical combination of ethinylestradiol (EE) and drospirenone (DSP)” (the 2004 patent).  A copy of the decision is provided here: DECISION.  The decision is important because the Court held that while it is possible to obtain parent and divisional patents in South Africa having overlapping claims of varying scope, coterminous claims (meaning claims of identical scope) are not permitted.

The claims of the 2004 patent relate to a female contraceptive sold by Bayer under the brand name Yasmin® which is a combination of the DSP and EE.  The 2004 patent is a divisional patent of South African Patent No. 2002/1668 (the 2002 patent).  Claim 1 of the 2004 patent recites:

1.  A pharmaceutical composition comprising:

as a first active agent drospirenone in an amount corresponding to a daily dosage, on administration of the composition, of  from about 2 mg to 4 mg, and

as a second active agent ethinylestradiol in an amount corresponding to a daily dosage of from about 0.01 mg to 0.05 mg,

together with one or more pharmaceutically acceptable carriers or excipients,

wherein at least 70% of said drospirenone is dissolved from said composition within 30 minutes, as determined by USP XXIII Paddle Method II using water at 37ºC as the dissolution media and 50 rpm as the stirring rate.

In contrast, claim 1 of the 2002 patent recites that the drospirenone is in micronized form.

In March 2011, Pharma obtained approval from the Medical Control Council in South Africa to import and sell “Ruby”, a generic version of Yasmin®.  Bayer alleged infringement of claim 1 of the 2004 patent by Pharma and sought judicial relief in the form of an interdict and ancillary relief.  Pharma denied infringement and counterclaimed for revocation of the 2004 patent alleging invalidity.  The lower court, a quo, held that the 2004 patent was valid and infringed by Pharma.  The relief requested by Bayer was granted and Pharma’s counterclaim dismissed.  Pharma appealed.  On appeal, regarding invalidity, Pharma argued that the 2004 patent lacked inventive step and was not a “true” divisional of the 2002 patent and thus lacked novelty in view of the disclosure in the 2002 patent.

In South Africa, divisional patent applications are governed by Section 37 of the Patents Act (Section 37) which provides:

1.  Where at any time after an application has been lodged at the patent office and before it is accepted, a fresh application is made in the prescribed manner by the same applicant in respect of part of the matter disclosed in the first-mentioned application, the registrar may, on application made to him in the prescribed manner before that application is accepted, direct that such fresh application be antedated to a date not earlier than the date on which the first-mentioned application was so lodged.

2.  A patent granted on such fresh application shall not be revoked or invalidated on the ground only that the invention claimed in such fresh application is not new having regard to the matter disclosed in the first-mentioned application.

Pharma made several arguments as to why it believed the 2004 patent was not a “true” divisional.  Specifically, Pharma argued that the “body”and the claims of the 2002 and 2004 patents were the same,  and that Section 37 did not allow for a divisional claim to be broader than the claim of its parent.

The Supreme Court rejected all of Pharma’s arguments. First, the Court noted that the very idea of a divisional patent is that it contains the same text as its parent.  From a practical standpoint, this made sense since the invention disclosed in a divisional and parent was the same and the difference between the two resided in their respective claims.  Next, the Court stated that the claims of the 2002 and 2004 patents were not coterminus (namely, the claims of each did not have identical scope).  Specifically, claim 1 of the 2002 patent was expressly limited to DSP in micronized form.  Claim 1 of the 2004 patent did not recite that DSP was limited to any specific form.  Thus, claim 1 of the 2004 patent was broader than claim 1 of the 2002 patent. Finally, the Court examined previous case law and found that there was nothing that prohibited the claims of a divisional application from being broader than the claims of its parent.  Instead, the Court noted that previous case law stood for the proposition that the claims of a divisional application could not be broader than the invention disclosed in the “body” of its parent.

Under South African patent law, a single invalid claim in a patent renders the entire patent invalid and unenforceable until such invalidity has been cured via an amendment.  Therefore, in view of this recent decision and the fact that patent applications are not formally examined in South Africa, applicants should carefully review the claims of any of their divisional patent applications and patents to make sure that none of the claims is identical in scope (coterminus) with one or more parent applications or patents.