except the person giving the testimony, the attorney for and any other representative of the person giving the testimony, the attorney for the Government, any person who may be agreed upon by the attorney for the Government and the person giving the testimony, the officer before whom the testimony is to be taken, and any stenographer taking such testimony. (3) Where testimony taken The oral testimony of any person taken pursuant to a civil investigative demand served under this section shall be taken in the judicial district of the United States within which such person resides, is found, or transacts business, or in such other place as may be agreed upon by the investigator conducting the examination and such person. (4) Transcript of testimony When the testimony is fully transcribed, the investigator or the officer before whom the testimony is taken shall afford the witness (who may be accompanied by counsel) a reasonable opportunity to examine and read the transcript, unless such examination and reading are waived by the witness. Any changes in form or substance which the witness desires to make shall be entered and identified upon the transcript by the officer or the investigator with a statement of the reasons given by the witness for making such changes. The transcript shall then be signed by the witness, unless the witness in writing waives the signing, is ill, cannot be found, or refuses to sign. If the transcript is not signed by the witness within 30 days after being afforded a reasonable opportunity to examine it, the officer or the investigator shall sign it and state on the record the fact of the waiver, illness, absence of the witness, or the refusal to sign, together with the reason, if any, given therefor. (5) Certification and delivery to custodian The officer before whom the testimony is taken shall certify on the transcript that the witness was duly sworn by the officer and that the transcript is a true record of the testimony given by the witness, and the officer or investigator shall