IP Cases & Articles

MedImmune v Novartis: Obviousness and Lack of Priority 

The judgment by Mr Justice Arnold runs to 161 pages, and relates to a large family of patents jointly owned by MedImmune and MRC, which were directed to antibody phage display technology. Allegedly these patents were infringed by Novartis’ sale of Lucentis (chemically named ranibizumab), which is a treatment for the eye condition wet age-related macular degeneration.

Novartis made a counter claim of invalidity, raising lack of priority, obviousness, insufficiency and added matter as attacks against the patents.


The Judge applied the reasoning from Virgin Atlantic Airways Ltd v Premium Aircraft Interiors UK Ltd [2009] (EWCA Civ 1062, [2010] RPC 8 at [5]) in order to construe the relevant claims. Essentially this judgment states that the first overarching principle is that contained in Article 69 of the European Patent Convention (EPC).

Article 69 EPC says that the extent of protection is determined by the claims and that the description and drawings shall be used to interpret the claims. In other words, the claims are to be construed in context. Following on from this, the claims are to be construed purposively, with the inventor's purpose being ascertained from the description and drawings. The claims must not be construed as if they stood alone.


The most important claims from two of the patents in question were asserted to not be entitled to priority from a document referred to as PD3, and as a result both patents were declared invalid. PD3 was judged not to directly and unambiguously teach the skilled person to the subject-matter of the relevant claims.

The 'skilled person' whose knowledge is crucial in deciding on the obviousness of a patent (or patent application during the application process) was in this case defined as a team. The Judge identified this team as consisting of an immunologist and a molecular biologist with experience of antibody engineering, protein chemistry and cell biology.


The Judge went on to assert that even if priority claim were to be valid, both of the most important patents would be obvious in view of a talk and accompanying slides given by a Professor Smith at a conference in 1990.

In the UK, we generally use the Pozolli test for obviousness, which consists of the following steps:

  1. (a) identify the notional ‘person skilled in the art’;
    (b) identify the relevant common general knowledge of that person;
  2. identify the inventive concept of the claim in question or if that cannot readily be done, construe it;
  3. identify what, if any, differences exist between the matter cited as forming part of the ‘state of the art’ and the inventive concept of the claim or the claim as construed;
  4. viewed without any knowledge of the alleged invention as claimed, do those differences constitute steps which would have been obvious to the person skilled in the art or do they require any degree of invention?”

When considering the fourth Pozzoli step above, it is usually considered relevant to whether what is claimed arises from taking a step which was obvious to try with a fair expectation of success.

In this case, Mr Justice Arnold was of the opinion that although Professor Smith’s talk at the Banbury Conference did not anticipate of any of the relevant claims this was only because Professor Smith had not actually got as far as testing an actual experiment involving antibody phage display. Therefore the judge considered there was no dispute that Professor Smith’s talk made it obvious to try phage display of antibodies. The only question is whether the talk would have given the skilled team a reasonable expectation of success within a reasonable time.

It was considered that Professor Smith gave the talk as a challenge, hoping to recruit other researchers to test his theories and proposed experiments. Therefore his overall message was a positive one, encouraging other to expect success.


MedImmune alleged that Novartis’ manufacturing process for ranibizumab fell within their claims, and that the ranibizumab so produced was a product obtained directly by means of that process. The process in question was carried out in the US, and therefore using the process did not infringe the UK patents. However, importing a product directly obtained from the patented process is grounds for infringement in the UK.

As the patents were declared invalid, no infringement could have occurred. However, the judge considered that, had the validity of the parent stood, Novartis’ products would have been considered to have been directly obtained by the process, despite further processing, as ranibizumab retained its essential characteristics.

The attacks based on insufficiency and added matter failed.


In summary, Novartis was triumphant due to a lack of clear priority, and obviousness due to a talk by a scientist.

This judgement emphasises that in order to validly claim priority, the priority document must clearly disclose the relevant subject-matter. The skilled person cannot be expected to make an inventive leap from the teaching of the priority document to arrive at the invention of the patent. Rather, they must be directly taught by the priority document in order for the claimed priority to stand.

This judgment also contains a very detailed background on the science of biological sequences (nucleic and amino acids) which may be of interest to scientists.

If you have any questions raised by this article, please contact your usual D Young & Co LLP adviser.

Useful link

Full text of decision:
MedImmune v (1) Novartis Pharmaceuticals UK Limited (2) Medical Research Council., 5 July 2011, England and Wales High Court (Patents Court), London, UK, Case No: HC09 C04770 [2011] EWHC 1669 (Pat)