(1) Basic rebate for single source drugs and innovator multiple source drugs (A) In general Except as provided in paragraph (2), the amount of the rebate specified in this subsection for a rebate period (as defined in subsection (k)(8)) with respect to each dosage form and strength of a single source drug or an innovator multiple source drug shall be equal to the product of— (i) the total number of units of each dosage form and strength paid for under the State plan in the rebate period (as reported by the State); and (ii) subject to subparagraph (B)(ii), the greater of— (I) the difference between the average manufacturer price and the best price (as defined in subparagraph (C)) for the dosage form and strength of the drug, or (II) the minimum rebate percentage (specified in subparagraph (B)(i)) of such average manufacturer price, for the rebate period. (B) Range of rebates required (i) Minimum rebate percentage For purposes of subparagraph (A)(ii)(II), the “minimum rebate percentage” for rebate periods beginning— (I) after December 31, 1990 , and before October 1, 1992 , is 12.5 percent; (II) after September 30, 1992 , and before January 1, 1994 , is 15.7 percent; (III) after December 31, 1993 , and before January 1, 1995 , is 15.4 percent; (IV) after December 31, 1994 , and before January 1, 1996 , is 15.2 percent; (V) after December 31, 1995 , and before January 1, 2010 is 15.1 percent; and (VI) except as provided in clause (iii), after December 31, 2009 , 23.1 percent. (ii) Temporary limitation on maximum rebate amount In no case shall the amount applied under subparagraph (A)(ii) for a rebate period beginning— (I) before January 1, 1992 , exceed 25 percent of the average manufacturer price; or (II) after December 31, 1991 , and before January 1, 1993 , exceed 50 percent of the average manufacturer price. (iii) Minimum rebate percentage for certain drugs (I) In general In the case of a single source drug or an innovator multiple source drug described in subclause (II), the minimum rebate percentage for rebate periods specified in clause (i)(VI) is 17.1 percent. (II) Drug described For purposes of subclause (I), a single source drug or an innovator multiple source drug described in this subclause is any of the following drugs: (aa) A clotting factor for which a separate furnishing payment is made under section 1395u(o)(5) of this title and which is included on a list of such factors specified and updated regularly by the Secretary. (bb) A drug approved by the Food and Drug Administration exclusively for pediatric indications. (C) “Best price” defined For purposes of this section— (i) In general The term “best price” means, with respect to a single source drug or innovator multiple source drug of a manufacturer (including the lowest price available to any entity for any such drug of a manufacturer that is sold under a new drug application approved under section 505(c) of the Federal Food, Drug, and Cosmetic Act [ 21 U.S.C. 355(c) ]), the lowest price available from the manufacturer during the rebate period to any wholesaler, retailer, provider, health maintenance organization, nonprofit entity, or governmental entity within the United States, excluding— (I) any prices charged on or after October 1, 1992 , to the Indian Health Service, the Department of Veterans Affairs, a State home receiving funds under section 1741 of title 38 , the Department of Defense, the Public Health Service, or a covered entity described in subsection (a)(5)(B) (including inpatient prices charged to hospitals described in section 256b(a)(4)(L) of this title ); (II) any prices charged under the Federal Supply Schedule of the General Services Administration; (III) any prices used under a State pharmaceutical assistance program; (IV) any depot prices and single award contract prices, as defined by the Secretary, of any agency of the Federal Government; (V) the prices negotiated from drug manufacturers for covered discount card drugs under an endorsed discount card program under section 1395w–141 of this title ; and (VI) any prices charged which are negotiated by a prescription drug plan under part D of subchapter XVIII, by an MA–PD plan under part C of such subchapter with respect to covered part D drugs or by a qualified retiree prescription drug plan (as defined in section 1395w–132(a)(2) of this title ) with respect to such drugs on behalf of individuals entitled to benefits under part A or enrolled under part B of such subchapter, or any discounts provided by manufacturers under the Medicare coverage gap discount program under section 1395w–114a of this title . (ii) Special rules The term “best price”— (I) shall be inclusive of cash discounts, free goods that are contingent on any purchase requirement, volume discounts, and rebates (other than rebates under this section); (II) shall be determined without regard to special packaging, labeling, or identifiers on the dosage form or product or package; (III) shall not take into account prices that are merely nominal in amount; and (IV) in the case of a manufacturer that approves, allows, or otherwise permits any other drug of the manufacturer to be sold under a new drug application approved under section 505(c) of the Federal Food, Drug, and Cosmetic Act [ 21 U.S.C. 355(c) ], shall be inclusive of the lowest price for such authorized drug available from the manufacturer during the rebate period to any manufacturer, wholesaler, retailer, provider, health maintenance organization, nonprofit entity, or governmental entity within the United States, excluding those prices described in subclauses (I) through (IV) of clause (i). (iii) Application of auditing and recordkeeping requirements With respect to a covered entity described in section 256b(a)(4)(L) of this title , any drug purchased for inpatient use shall be subject to the auditing and recordkeeping requirements described in section 256b(a)(5)(C) of this title . (D) Limitation on sales at a nominal price (i) In general For purposes of subparagraph (C)(ii)(III) and subsection (b)(3)(A)(iii)(III), only sales by a manufacturer of covered outpatient drugs at nominal prices to the following shall be considered to be sales at a nominal price or merely nominal in amount: (I) A covered entity described in section 256b(a)(4) of this title . (II) An intermediate care facility for the mentally retarded. (III) A State-owned or operated nursing facility. (IV) An entity that— (aa) is described in section 501(c)(3) of the Internal Revenue Code of 1986 and exempt from tax under section 501(a) of such Act or is State-owned or operated; and (bb) would be a covered entity described in section 256b(a)(4) 1 of this title insofar as the entity provides the same type of services to the same type of populations as a covered entity described in such section provides, but does not receive funding under a provision of law referred to in such section; (V) A public or nonprofit entity, or an entity based at an institution of higher learning whose primary purpose is to provide health care services to students of that institution, that provides a service or services described under section 300(a) of this title . (VI) Any other facility or entity that the Secretary determines is a safety net provider to which sales of such drugs at a nominal price would be appropriate based on the factors described in clause (ii). (ii) Factors The factors described in this clause with respect to a facility or entity are the following: (I) The type of facility or entity. (II) The services provided by the facility or entity. (III) The patient population served by the facility or entity. (IV) The number of other facilities or entities eligible to purchase at nominal prices in the same service area. (iii) Nonapplication Clause (i) shall not apply with respect to sales by a manufacturer at a nominal price of covered outpatient drugs pursuant to a master agreement under section 8126 of title 38 . (iv) Rule of construction Nothing in this subparagraph shall be construed to alter any existing statutory or regulatory prohibition on services with respect to an entity described in clause (i)(IV), including the prohibition set forth in section 300a–6 of this title .