Commingling of pari-mutuel pools occurs when all wagers which are made, both within and outside of Maryland on a specific pari-mutuel pool, are combined for the purpose of determining a payout. For the purpose of this regulation: “Gross pool” means the total monies accumulated in a specific wagering pool before the deduction of the applicable takeout as prescribed by the law in the jurisdiction in which the wagers take place. “Net pool” means the total monies accumulated in a specific wagering pool after the deduction of the applicable takeout as prescribed by the law in the jurisdiction in which the wagers take place. When an association in Maryland is permitted to commingle the wagers made in Maryland on a race in another jurisdiction with the wagers made at the association in the other jurisdiction, and the public is notified that commingling is taking place, the winning wagers shall be paid at the price determined by the odds posted at the association where the live race took place except, once wagering has begun and circumstances prevent the commingling from being accomplished, there shall be a refund of all these wagers made at the Maryland association, if: A public announcement is made by the Maryland association not less than 2 minutes before the post time of the race that commingling cannot be accomplished, when the wager involves only one race; or The wager involves more than one race, and a public announcement is made by the Maryland association that commingling cannot be accomplished: By the off time of the first race of the wager, or Not more than 10 minutes after the finish of the first race of the wager, unless there is a payoff due on a wager as a result of the first race. If a payoff is due under the exception to §C(2)(b) of this regulation, there is no refund and the payoff shall be multiplied by a number which would make the sum of the payoff of all winning wagers on the first race of the pool equal to the net pool on that wager, exclusive of any carryover. An association in Maryland shall request and receive permission from the Commission before entering into a commingling agreement with an entity, or entities, in other jurisdictions. The request shall include the method of commingling to be used, that is, the net pool method or the gross pool method. If the net pool method is employed, the Maryland association shall apply the base payout price to the winning wagers in the Maryland association's pool to determine the payout on these wagers. If the gross pool method of commingling is used, the takeout on wagers placed in Maryland is the same as the takeout used at the association at which the live race takes place. Underpayment or Overpayment. When a payoff is required under §C or D of this regulation, a resulting underpayment or overpayment of the distributable pools shall be accumulated to determine a net overpayment or underpayment. Within 10 days after the end of the calendar year, the association shall report a net underpayment for the year to the Commission, and the association shall add the net underpayment to future distributable pools as directed by the Commission. If there is a net overpayment at the end of the calendar year, it may be carried forward to the succeeding calendar year and shall become a part of the accumulation for that calendar year. When wagers on a race or races are commingled, the regulations in the jurisdiction where the race or races take place shall be used in administering the wager.