definiens: means an accounting firm of national reputation in the United States ( excluding each ofAstraZeneca ’s and Horizon ’s respective regular outside accounting firms ) as may be mutually acceptable toAstraZeneca and Horizon ; provided, however, if [COMPANY] and Horizon are unable to agree on such accounting firmwithin 10 days or any such mutually selected accounting firm is unwilling or unable to serve, then [COMPANY] shalldeliver to Horizon a list of three other accounting firms of national reputation in the United States that have notperformed services for [COMPANY] or Horizon in the preceding three - year period, and Horizon shall select one ofsuch three accounting firms.1.1.2 means all accounts receivable, notes receivable and other indebtedness dueand owed by any Third Party to [COMPANY] or any of its Affiliates arising from sales of the Product by or on behalfof [COMPANY] or its Affiliates in the Horizon Territory prior to the Closing Date