2 U.S.C. § 1610 - Estimates based on tax reporting system

2 USC 1610 - Estimates based on tax reporting system

(a) Entities covered by section 6033 (b) of title 26 
A person, other than a lobbying firm, that is required to report and does report lobbying expenditures pursuant to section 6033 (b)(8) of title 26 may
(1) make a good faith estimate (by category of dollar value) of applicable amounts that would be required to be disclosed under such section for the appropriate quarterly period to meet the requirements of sections 1603 (a)(3) and 1604 (b)(4) of this title; and
(2) for all other purposes consider as lobbying contacts and lobbying activities only
(A) lobbying contacts with covered legislative branch officials (as defined in section 1602 (4) of this title) and lobbying activities in support of such contacts; and
(B) lobbying of Federal executive branch officials to the extent that such activities are influencing legislation as defined in section 4911 (d) of title 26.
(b) Entities covered by section 162 (e) of title 26 
A person, other than a lobbying firm, who is required to account and does account for lobbying expenditures pursuant to section 162 (e) of title 26 may
(1) make a good faith estimate (by category of dollar value) of applicable amounts that would not be deductible pursuant to such section for the appropriate quarterly period to meet the requirements of sections 1603 (a)(3) and 1604 (b)(4) of this title; and
(2) for all other purposes consider as lobbying contacts and lobbying activities only
(A) lobbying contacts with covered legislative branch officials (as defined in section 1602 (4) of this title) and lobbying activities in support of such contacts; and
(B) lobbying of Federal executive branch officials to the extent that amounts paid or costs incurred in connection with such activities are not deductible pursuant to section 162 (e) of title 26.
(c) Disclosure of estimate 
Any registrant that elects to make estimates required by this chapter under the procedures authorized by subsection (a) or (b) of this section for reporting or threshold purposes shall
(1) inform the Secretary of the Senate and the Clerk of the House of Representatives that the registrant has elected to make its estimates under such procedures; and
(2) make all such estimates, in a given calendar year, under such procedures.
(d) Study 
Not later than March 31, 1997, the Comptroller General of the United States shall review reporting by registrants under subsections (a) and (b) of this section and report to the Congress
(1) the differences between the definition of lobbying activities in section 1602 (7) of this title and the definitions of lobbying expenditures, influencing legislation, and related terms in sections 162 (e) and 4911 of title 26, as each are implemented by regulations;
(2) the impact that any such differences may have on filing and reporting under this chapter pursuant to this subsection; and
(3) any changes to this chapter or to the appropriate sections of title 26 that the Comptroller General may recommend to harmonize the definitions.