The examiner must form an opinion as to whether or not the biological material is available to the public. There are several possibilities. The biological material may be known to be readily available to those skilled in the art, e.g. baker's yeast or Bacillus natto, which is commercially available, it may be a standard preserved strain, or other biological material which the examiner knows to have been preserved in a recognised depository and to be available to the public. Alternatively, the applicant may have given in the description sufficient information as to the identifying characteristics of the biological material and as to the prior availability in a depositary institution recognised for the purposes of Rule 33(6) to satisfy the examiner. In any of these cases no further action is called for. If, however, the applicant has given no or insufficient information on public availability and the biological material is a particular strain not falling within the known categories such as those already mentioned, then the examiner must assume that the biological material is not available to the public. He must also examine whether the biological material could be described in the European patent application in such a manner as to enable the invention to be carried out by a person skilled in the art (see, in particular, II, 4.11 and IV, 4.7).