Tuesday, 3 November 2009

T 891/05 - One For All and All But One

The present decision shows that a “precautionary disclaimer” is not acceptable before the EPO. One cannot excise features on the basis of the conviction that there is prior art. Quite to the contrary, the disclaimed portion must correspond to a well identified piece of prior art.

[…] The expression in claim 19 [as granted] “more than one and fewer than all” of a variable number of word line segments introduces the concepts of two as a minimum and all-but-one as a maximum, which are not directly and unambiguously derivable from the application as originally filed.

The patentee has argued that activating all word line segments or sets of sense amplifiers was prior art, and that removing a feature from a claim did not contravene A 123(2) if its substitute could be prior art.

The board is not convinced by this argument. Whilst, under certain conditions, an undisclosed disclaimer may be allowable without contravening A 123(2), the present case does not fulfil these conditions, since, for instance, the patentee has not identified a specific piece of prior art that this amendment disclaims. [4.5]

To read the whole decision, click here.