19 CFR § 113.35 - Individual sureties.
(a) Number required. If individuals sign as sureties, there must be two sureties on the bond unless CBP is satisfied that one surety is sufficient to protect the revenue and ensure compliance with the law and regulations.
(b) Qualifications to act as surety—(1) Residency and citizenship. Each individual surety on a CBP bond must be both a resident and citizen of the United States.
(2) Granting of power of attorney. Any individual, unless prohibited by law, may grant a power of attorney to sign as surety on CBP bonds. Unless the power is unlimited, all persons to whom the power relates must be named.
(3) Property requirements. For both single transaction and continuous bonds, each individual surety must have property available as security within the customs territory of the United States. The current market value of the property, less any encumbrance, must be equal to or greater than the amount of the bond. If one individual surety is accepted, the individual surety must have property the value of which, less any encumbrance, is equal to or greater than twice the amount of the bond.
(c) Oath and evidence of solvency. Before being accepted as a surety, the individual must:
(1) Take an oath on CBP Form 3579, setting forth:
(i) The amount of assets over and above all debts and liabilities and such exemptions as may be allowed by law; and
(ii) The general description and location of one or more pieces of real estate owned within the customs territory of the United States, and the value thereof, less any encumbrance.
(2) Produce such evidence of solvency and financial responsibility as CBP may require.
(d) Determination of financial responsibility. An individual will not be accepted as surety on a bond until CBP is satisfied as to the financial responsibility of the individual. CBP may request Immigration and Customs Enforcement (ICE) to conduct an immediate investigation to verify a surety's financial responsibility.
(e) Continuancy of financial responsibility. In order to ascertain the continued solvency and financial responsibility of individual sureties, CBP will require a new oath and determine the financial responsibility of each individual surety as prescribed in paragraphs (c) and (d) of this section at least once every six months, and more often if deemed advisable.