One can never have too many patent judgments ...

Teva UK Ltd v Merck & Co, Inc [2009] EWHC 2952 (Pat) (20 november) is one of those patent cases that looks as if it will teach you more about the science involved (in this case, treatments for glaucoma) than about the law. it involves questions about amendments to a patent, added matter and inventive step, runs to 164 paragraphs and concludes (in the judge's precise words):

i) the Patent as proposed to be amended is invalid for lack of inventive step;

ii) had the Patent as proposed to be amended not been invalid, I would have allowed the amendment to claim 1, but not the amendment to claim 18 (which adds matter);

iii) unamended claims 1 to 6 and 8 to 9 lacked inventive step;

iv) unamended claim 20 added matter.

I'll see if there is more to it than has met my eye so far.