It has been the practice of the European Patent Office to permit an amendment of claims during prosecution so as to overcome an objection of lack of novelty, although not normally an objection of lack of inventive step, by specifically disclaiming that which was disclosed in the prior art, irrespective of whether the language of one's own application provided a specific basis for that disclaimer. A so-far unreported decision, Disclaimer/Unilever, will change this. The new decision holds that, like all other amendments permitted under the European Patent Convention, there must be support in the application as filed for any disclaimer that one subsequently wishes to introduce into the claims.