(a) General rule. In lieu of taking a deduction under section 616(a), in the taxable year when the development expenditures are paid or incurred, a taxpayer may elect under section 616(b) to treat such expenditures with respect to each mine or other natural deposit as deferred expenses to be deducted ratably as the units of the produced ore or minerals benefited by such expenditures are sold. Section 616(b) is applicable to development expenditures paid or incurred both in the development and producing stage of the mine or other natural deposit. However, in the case of such expenditures made in the development stage, this election is applicable only to the excess of the amount of such expenditures over the net receipts from the ore or minerals from such mine or deposit received or accrued during the development stage and in the same taxable year as the expenditures were paid or incurred. Such development expenditures not in excess of such net receipts shall be subject to the provisions of section 616(a).

(b) Producing stage; definition of. The mine or other natural deposit will be considered to be in a producing stage when the major portion of the mineral production is obtained from workings other than those opened for the purpose of development, or when the principal activity of the mine or other natural deposit is the production of developed ores or minerals rather than the development of additional ores or minerals for mining.

(c) Expenditures made by the owner who retains a nonoperating interest.

(1) A taxpayer who elects to defer development expenditures and thereafter transfers his interest in the mine or other natural deposit, retaining an economic interest therein, shall deduct an amount attributable to such interest on a pro rata basis as the interest pays out. For example, a taxpayer who defers development expenditures and then leases his deposit, retaining a royalty interest therein, shall deduct the deferred expenditures ratably as he receives the royalties. If the taxpayer receives a bonus or advanced royalties in connection with the transfer of his interest, he shall deduct the deferred expenditures allocable to such bonus or advanced royalties in an amount which is in the same proportion to the total of such costs as the bonus or advanced royalties bears to the bonus and total royalties expected to be received. Also, in the case of a transfer of a mine or other natural deposit by a taxpayer who retains a production payment therein, he may deduct the development expenditures ratably over the payments expected to be received.

(2) Where a taxpayer receives an amount, in addition to retaining an economic interest, which amount is treated as from the sale or exchange of a capital asset or property treated under section 1231 (except coal or iron ore to which section 631(c) applies), the deferred development expenditures shall be allocated between the interest sold and the interest retained in proportion to the fair market value of each interest as of the date of sale. The amount allocated to the interest sold may not be deducted, but shall be a part of the basis of such interest for the purpose of determining gain or loss upon the sale thereof.

(d) Losses from abandonment. Section 165 and the regulations thereunder contain general rules relating to the treatment of losses resulting from abandonment.

(e) Effect of election.

(1) The election to defer development expenditures shall apply only to expenditures for the taxable year for which made. However, once made, the election shall be binding with respect to the expenditures for that taxable year. Thus, a taxpayer cannot revoke his election for any reason whatsoever.

(2) The election shall be made for each mine or other natural deposit by a clear indication on the return or by a statement filed with the district director with whom the return was filed, not later than the time prescribed by law for filing such return (including extensions thereof) for the taxable year to which such election is applicable.

(f) Computation of amount of deduction. The amount of the deduction allowable during the taxable year is an amount A, which bears the same ratio to B (the total deferred development expenditures for a particular mine or other natural deposit reduced by the amount of such expenditures deducted in prior taxable years) as C (the number of units of the ore or mineral benefited by such expenditures sold during the taxable year) bears to D (the number of units of ore or mineral benefited by such expenditures remaining as of the taxable year). For the purposes of this proportion, the number of units of ore or mineral benefited by such expenditures remaining as of the taxable year is the number of units of ore or mineral benefited by the deferred development expenditures remaining at the end of the year to be recovered from the mine or other natural deposit (including units benefited by such expenditures recovered but not sold) plus the number of units benefited by such expenditures sold within the taxable year. The principles outlined in §1.611-2 are applicable in estimating the number of units remaining as of the taxable year and the number of units sold during the taxable year. The estimate is subject to revision in accordance with that section in the event it is ascertained, from any source, such as operations or development work, that the remaining units are materially greater or less than the number of units remaining from a prior estimate.

[T.D. 6500, 25 FR 11737, Nov. 26, 1960, as amended by T.D. 6841, 30 FR 9307, July 27, 1965]