CFR > Title 37 - Patents, Trademarks, and Copyrights > CHAPTER I—UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE > PART 10—REPRESENTATION OF OTHERS BEFORE THE PATENT AND TRADEMARK OFFICE > 10.92—Contact with witnesses.

10.92—Contact with witnesses.

(a) A practitioner shall not suppress any evidence that the practitioner or the practitioner's client has a legal obligation to reveal or produce.
(b) A practitioner shall not advise or cause a person to be secreted or to leave the jurisdiction of a tribunal for the purpose of making the person unavailable as a witness therein.
(c) A practitioner shall not pay, offer to pay, or acquiesce in the payment of compensation to a witness contingent upon the content of the witness' affidavit, testimony or the outcome of the case. But a practitioner may advance, guarantee, or acquiesce in the payment of:
(1) Expenses reasonably incurred by a witness in attending, testifying, or making an affidavit.
(2) Reasonable compensation to a witness for the witness' loss of time in attending, testifying, or making an affidavit.
(3) A reasonable fee for the professional services of an expert witness.