For example, gross investment income includes amounts received as commitment fees, or as a bonus for the entering into of a lease, or as a penalty for the early payment of a mortgage. In computing the gross income from any trade or business (other than an insurance business) carried on by the insurance company, or by a partnership of which the insurance company is a partner, any item described in section 822(b)(1) and paragraph (b)(1) of this section shall not be considered as gross income arising from the conduct of such trade or business, but shall be taken into account under section 822(b)(1) and paragraph (b)(1) of this section.
For purposes of section 822(c)(2) and this paragraph, the term "invested assets" means only those assets which are owned and used, and to the extent used, for the purpose of producing the income specified in section 822(b). See paragraph (b) of this section. The term does not include real estate owned and occupied, and to the extent owned and occupied, by the company.
26 C.F.R. §1.822-5