(a) There is excluded any gain or loss: (1) Which is considered as gain or loss from the sale or exchange of a capital asset; (2) from the cutting of timber or the disposal of timber, coal, or iron ore, even though held primarily for sale to customers, if section 631 is applicable to such gain or loss; and (3) from the sale, exchange, involuntary conversion, or other disposition of property if such property is neither (i) stock in trade or other property of a kind which would properly be includible in inventory if on hand at the close of the taxable year, nor (ii) property held primarily for sale to customers in the ordinary course of a trade or business. For the purpose of the special rule in subparagraph (3) of this paragraph, it is immaterial whether a gain or loss is treated as a capital gain or loss or as an ordinary gain or loss for purposes other than determining net earnings from self-employment. For instance, where the character of a loss is governed by the provisions of section 1231, such loss is excluded in determining net earnings from self-employment even though such loss is treated under section 1231 as an ordinary loss. For the purposes of this special rule, the term “involuntary conversion” means a compulsory or involuntary conversion of property into other property or money as a result of its destruction in whole or in part, theft or seizure, or an exercise of the power of requisition or condemnation or the threat or imminence thereof; and the term “other dispostion” includes the destruction or loss, in whole or in part, of property by fire, storm, shipwreck, or other casualty, or by theft, even though there is no conversion of such property into other property or money.

(b) The application of this section may be illustrated by the following example: