From the SEC Enforcement Manual:
"The written Wells notice or written confirmation of an oral Wells notice should:
• identify the specific charges the staff is considering recommending to the
Commission;
• accord the recipient of the Wells notice the opportunity to provide a voluntary
statement, in writing or on videotape, arguing why the Commission should not bring
an action against them or bringing any facts to the Commission’s attention in
connection with its consideration of this matter;
• set reasonable limitations on the length of any submission made by the recipient
(typically, written submissions should be limited to 40 pages, not including exhibits,
and video submissions should not exceed 12 minutes), as well as the time period
allowed for the recipients to submit a voluntary statement in response to the Wells
notice;
Note that the time is not specified.