(a) In general. This section provides rules describing basis difference that is not taken into account under section 901(m) because a CAA results in a de minimis amount of basis difference. Paragraph (b) of this section sets forth the general rule for determining whether the de minimis threshold is met. Paragraph (c) of this section modifies the general rule in the case of CAAs that are part of an aggregated CAA transaction. Paragraph (d) of this section provides rules for applying this section, and paragraph (e) of this section provides an anti-abuse rule applicable to related persons. Paragraph (f) of this section provides examples that illustrate the application of this section. Paragraph (g) of this section provides applicability dates.

(b) General rule—(1) In general. A basis difference with respect to an RFA and a foreign income tax is not taken into account under section 901(m) if the requirements under the cumulative basis difference exemption, the RFA class exemption, or the RFA exemption are satisfied.

(2) Cumulative basis difference exemption. Except as provided in paragraph (c) of this section, a basis difference, with respect to an RFA and a foreign income tax, is not taken into account under section 901(m) (cumulative basis difference exemption) if the sum of that basis difference and all other basis differences (including negative basis differences), with respect to a single CAA and a single RFA owner (U.S.), is less than the greater of:

(i) $10 million, or

(ii) 10 percent of the total U.S. basis of all the RFAs immediately after the CAA.

(3) RFA class exemption—(i) Except as provided in paragraph (c) of this section, a basis difference, with respect to an RFA and a foreign income tax, is not taken into account under section 901(m) (RFA class exemption) if the RFA is part of a class of RFAs and the absolute value of the sum of the basis differences (including negative basis differences), with respect to a single CAA and a single RFA owner, for all the RFAs in that class is less than the greater of:

(A) $2 million, or

(B) 10 percent of the total U.S. basis of all the RFAs in that class of RFAs immediately after the CAA.

(ii) For purposes of this paragraph (b)(3), the classes of RFAs are the seven asset classes defined in § 1.338-6(b), regardless of whether the CAA is a section 338 CAA.

(4) RFA exemption. A basis difference, with respect to an RFA and a foreign income tax, is not taken into account under section 901(m) (RFA exemption) if the absolute value of the basis difference with respect to the RFA is less than $20,000.

(c) Special rule if a CAA is part of an aggregated CAA transaction. If a CAA is part of an aggregated CAA transaction and a single RFA owner (U.S.) does not own all the RFAs attributable to the CAAs that are part of the aggregated CAA transaction, the cumulative basis difference exemption and the RFA class exemption apply to such CAA only if, in addition to satisfying the requirements of paragraph (b)(2) or (b)(3) of this section, respectively, determined without regard to this paragraph (c), the cumulative basis difference exemption or the RFA class exemption, as modified by this paragraph (c), is satisfied. Solely for purposes of this paragraph (c), the cumulative basis difference exemption and the RFA class exemption are applied taking into account all the basis differences with respect to all the RFAs owned by all the RFA owners (U.S.) that are attributable to the CAAs that are part of the aggregated CAA transaction.

(d) Rules of application. The following rules apply for purposes of this section.

(1) Whether a basis difference qualifies for the cumulative basis difference exemption, the RFA class exemption, or the RFA exemption is determined when an asset first becomes an RFA with respect to a CAA. In the case of a subsequent CAA described in § 1.901(m)-6(b)(4), the application of the cumulative basis difference exemption, the RFA class exemption, and the RFA exemption is based on basis difference, if any, that results from the subsequent CAA.

(2) If there is an aggregated CAA transaction, the cumulative basis difference exemption and each RFA class exemption are applied by treating all CAAs that are part of the aggregated CAA transaction as a single CAA.

(3) Basis difference is computed in accordance with § 1.901(m)-4 except that a foreign basis election need not be evidenced if the cumulative basis difference exemption, an RFA class exemption, or the RFA exemption apply to all RFAs with respect to the CAA.

(4) Basis difference is translated into U.S. dollars (if necessary) using the spot rate determined under the principles of § 1.988-1(d) on the date of the CAA.

(e) Anti-abuse rule. The cumulative basis difference exemption, an RFA class exemption, and the RFA exemption are not available if the transferor and transferee in the CAA are related persons (as described in section 267(b) or 707(b)) and the CAA was entered into, or structured, with a principal purpose of avoiding the application of section 901(m). See also § 1.901(m)-8(c), which provides that certain built-in loss assets are not taken into account for purposes of applying this section.

(f) Examples. The following examples illustrate the rules of this section:

(1) Example 1: De minimis; cumulative basis difference exemption—(i) Facts. USP, a domestic corporation, as part of a plan, purchases all of the stock of CFC1 and CFC2 from a single seller. CFC1 and CFC2 are applicable foreign corporations, organized in Country F, and treated as corporations for Country F tax purposes. Country F imposes a single tax that is a foreign income tax. Each acquisition is a qualified stock purchase (as defined in section 338(d)(3)) to which section 338(a) applies. A foreign basis election is not made under § 1.901(m)-4(c). Immediately after the acquisition of the stock of CFC1 and CFC2, the assets of CFC1 and CFC2 give rise to income that is taken into account for Country F tax purposes, and those assets are in a single class, as defined in § 1.338-6(b). Assume that the absolute value of the basis difference with respect to any single RFA is greater than $20,000. At all relevant times, 1u equals $1. All amounts are stated in millions. The additional facts are summarized below.

(ii) Result. (A) Under § 1.901(m)-2(b)(1), USP's acquisitions of the stock of CFC1 and CFC2 are each a section 338 CAA. Under 1.901(m)-1(a)(3), the two section 338 CAAs constitute an aggregated CAA transaction because the acquisitions occur as part of a plan. Under § 1.901(m)-2(c)(1), the assets of CFC1 and CFC2 are RFAs for Country F tax purposes because they are relevant in determining foreign income of CFC1 and CFC 2, respectively, for Country F tax purposes. Under § 1.901(m)-1(a)(37), CFC1 is the RFA owner (U.S.) with respect to its assets, and CFC2 is the RFA owner (U.S.) with respect to its assets.

(B) Under paragraph (b)(2) of this section, the application of the cumulative basis difference exemption is based on a single CAA and a single RFA owner (U.S.), subject to the requirements under paragraph (c) of this section that apply when there is an aggregated CAA transaction. In the case of the section 338 CAA with respect to CFC1, without regard to paragraph (c) of this section, the requirements of the cumulative basis difference exemption are satisfied if the sum of the basis differences is less than the threshold of $10 million, the greater of $10 million or $6 million (10% of the total U.S. basis of $60 million (60 million u translated into dollars at the exchange rate of $1 = 1u)). In this case, the sum of the basis differences is $12 million (12 million u translated into dollars at the exchange rate of $1 = 1 u). Because the sum of the basis differences of $12 million is not less than the threshold of $10 million, the requirements of the cumulative basis difference exemption are not satisfied. Because the requirements of the cumulative basis difference exemption are not satisfied, without regard to paragraph (c) of this section, paragraph (c) of this section is not applicable. The RFA class exemption is not relevant because all of the RFAs of CFC1 are in a single class. Finally, because the absolute value with respect to each RFA is greater than $20,000, the RFA exemption does not apply. Accordingly, the basis differences with respect to all of the RFAs of CFC1 must be taken into account under section 901(m).

(C) In the case of the section 338 CAA with respect to CFC2, without regard to paragraph (c) of this section, the requirements of the cumulative basis difference exemption are satisfied if the sum of the basis differences is less than the threshold of $10 million, the greater of $10 million or $ 9.6 million (10% of the total U.S. basis of $96 million (96 million u translated into dollars at the exchange rate of $1 = 1u)) In this case, the sum of the basis differences is ($4) million ((4) million u translated into dollars at the exchange rate of $1 = 1 u). Because the sum of the basis differences of ($4) million is less than the threshold of $10 million, the requirements of the cumulative basis difference exemption are satisfied. However, because the section 338 CAA with respect to CFC2 is part of an aggregated CAA transaction that includes the section 338 CAA with respect to CFC1, paragraph (c) of this section is applicable. Under paragraph (c) of this section, the requirements of the cumulative basis difference exemption must also be satisfied taking into account all of the RFAs of both CFC2 and CFC1. In this case, the requirements of the cumulative basis difference exemption for purposes of paragraph (c) of this section are satisfied if the sum of the basis differences with respect to all of the RFAs of CFC2 and CFC1 is less than the threshold of $15.6 million, the greater of $10 million or $15.6 million (10% of the total U.S. basis of $156 million (156 million u translated into dollars at the exchange rate of $1 = 1u)). In this case, the sum of the basis differences is $8 million (8 million u translated into dollars at the exchange rate of $1 = 1 u). Because the sum of the basis differences of $8 million is less than the threshold of $15.6 million, the requirements of the cumulative basis difference exemption are satisfied in the case of the section 338 CAA with respect to CFC2. Accordingly, none of the basis differences with respect to the RFAs of CFC2 are taken into account under section 901(m).

(2) Example 2: De minimis; RFA Class Exemption—(i) Facts. USP, a domestic corporation, acquires all the stock of CFC, an applicable foreign corporation organized in Country F and treated as a corporation for Country F tax purposes, in a qualified stock purchase (as defined in section 338(d)(3)) to which section 338(a) applies. Country F imposes a single tax that is a foreign income tax. A foreign basis election is not made under § 1.901(m)-4(c). Immediately after the acquisition of CFC, the assets of CFC give rise to income that is taken into account for Country F tax purposes. Assume that the absolute value of the basis difference with respect to any single RFA is greater than $20,000. At all relevant times, 1u equals $1. All amounts are stated in millions. The additional facts are summarized below.

(ii) Result. (A) Under § 1.901(m)-2(b)(1), USP's acquisition of the stock of CFC is a section 338 CAA. Under § 1.901(m)-2(c)(1), the assets of CFC are RFAs for Country F tax purposes because they are relevant in determining foreign income of CFC for Country F tax purposes.

(B) Under paragraph (b)(2) of this section, the requirements of the cumulative basis difference exemption are satisfied if the sum of the basis differences is less than the threshold of $10 million, the greater of $10 million or $5.5 million (10% of the total U.S. basis of $55 million (55 million u translated into dollars at the exchange rate of $1 = 1u)). In this case, the sum of the basis differences is $12 million (12 million u translated into dollars at the exchange rate of $1 = 1 u). Because the sum of the basis differences of $12 million is not less than the threshold of $10 million, the requirements of the cumulative basis difference exemption are not satisfied.

(C) Under paragraph (b)(3) of this section, each of CFC's assets is allocated to its class under § 1.338-6(b) for purposes of the RFA class exemption. The requirements of the RFA class exemption with respect to the Class IV RFAs (in this case, inventory) are satisfied if the absolute value of the sum of the basis differences with respect to the Class IV RFAs is less than the threshold of $2 million, the greater of $2 million or $1.5 million (10% of the total U.S. basis of Class IV RFAs of $15 million (15 million u translated into dollars at the exchange rate of $1 = 1u)). In this case, the absolute value of the sum of the basis differences is $1 million (1 million u translated into dollars at the exchange rate of $1 = 1 u). Because the sum of the basis differences of $1 million is less than the threshold of $2 million, the requirements of the RFA class exemption are satisfied. Accordingly, the basis differences with respect to the Class IV RFAs are not taken into account under section 901(m).

(D) The requirements of the RFA class exemption with respect to the Class V RFAs (in this case, buildings) is satisfied if the absolute value of the sum of the basis differences with respect to the Class V RFAs is less than the threshold of $3 million, the greater of $2 million or $3 million (10% of the total U.S. basis of Class V RFAs of $30 million (30 million u translated into dollars at the exchange rate of $1 = 1u)). In this case, the absolute value of the sum of the basis differences is $11 million (11 million u translated into dollars at the exchange rate of $1 = 1 u). Because the sum of the basis differences of $11 million is not less than the threshold of $3 million, the requirements of the RFA class exemption are not satisfied. Finally, because the absolute value with respect to each RFA is greater than $20,000, the RFA exemption does not apply. Accordingly, the basis differences with respect to the Class V RFAs are taken into account under section 901(m).

(E) The Class I RFAs (in this case, cash) are irrelevant because there are no basis differences with respect to those RFAs.

(g) Applicability dates. This section applies to CAAs occurring on or after March 23, 2020. Taxpayers may, however, choose to apply this section before the date this section is applicable provided that they (along with any persons that are related (within the meaning of section 267(b) or 707(b)) to the taxpayer)—

(1) Consistently apply this section, § 1.704-1(b)(4)(viii)(c)(4)(v) through (vii), § 1.901(m)-1, §§ 1.901(m)-3 through 1.901(m)-6 (excluding § 1.901(m)-4(e)), and § 1.901(m)-8 to all CAAs occurring on or after January 1, 2011, and consistently apply § 1.901(m)-2 (excluding § 1.901(m)-2(d)) to all CAAs occurring on or after December 7, 2016, on any original or amended tax return for each taxable year for which the application of the provisions listed in this paragraph (g)(1) affects the tax liability and for which the statute of limitations does not preclude assessment or the filing of a claim for refund, as applicable;

(2) File all tax returns described in paragraph (g)(1) of this section for any taxable year ending on or before March 23, 2020, no later than March 23, 2021; and

(3) Make appropriate adjustments to take into account deficiencies that would have resulted from the consistent application under paragraph (g)(1) of this section for taxable years that are not open for assessment.