definiens: ( including any diminution thereof ) shall mean the fair market value of the [COMPANY] Royalty Interest or the [COMPANY] Interest, as the case may be, determined as follows : If the Parties can not agree on the Fair Market Value within 30 days after the launch of the Directly Competitive Product, each Party shall promptly designate a reputable investment banking or appraisal firm of its choice ( which in the case of an investment bank shall not be the regular banker of the Party ) ( the or each an ), who will each be asked to provide its best, single number estimate of the applicable Fair Market Value ( the ), using a common set of assumptions provided by the Parties, or if the Parties can not agree, determined by the Appraisers . Each Party shall use its best efforts to cause its designated Appraiser to provide the Estimate not later than 30 days after the Parties or the Appraiser, as the case may be, have determined the common set of assumptions to be used