Source: https://ethics.wi.gov/Pages/CampaignFinance/ProhibitedContributions.aspx
Timestamp: 2019-04-22 16:38:28+00:00

Document:
Corporations, associations (cooperatives and unincorporated cooperative associations), labor unions, and American Indian tribes may not contribute to certain types of political committees in Wisconsin, including candidate committees. These groups may contribute to independent expenditure committees, referenda committees, and segregated fund accounts established by party committees and legislative campaign committees (Wis. Stat. § 11.1112).
Committees and conduits are prohibited from accepting contributions from foreign nationals (Wis. Stat. § 11.1208(4)) as defined by 52 United States Code § 30121. Committees may only accept contributions from U.S. Citizens and U.S. permanent residents (green card holders).
Open Date: If the legislature is not in session, a lobbyist may make a personal contribution beginning on the first day the legislator or candidate may begin circulating nomination papers (Wis. Stat. § 13.625(1m)(b)). April 15 is the first day for circulating nomination papers for the general election in the fall.
Close Date: The date of the election the legislator or candidate is participating in (Wis. Stat. § 13.625(1m)(b)).
Lobbyists may not contribute to current legislators or candidates for Assembly or Senate while the legislature is in session. Contributions may be made only after the final floor period has concluded, and the legislature must not be in special or extraordinary session (Wis. Stat. § 13.625(1m)(b)1).
Open Date: A lobbyist may make a personal contribution beginning on the first day the official or candidate may begin circulating nomination papers (Wis. Stat. § 13.625(1m)(b)). April 15 is the first day for circulating nomination papers for the general election in the fall.
Close Date: The date of the election the official or candidate is participating in (Wis. Stat. § 13.625(1m)(b)).
A lobbyist may furnish (deliver or convey) a campaign contribution on behalf of a PAC, conduit, or other person to a candidate for any office at any time. A lobbyist may make a personal contribution to a candidate for non-partisan office at any time. See guideline ETH-1250 for more information.
Committees may not accept anonymous contributions exceeding $10. If a committee does accept an anonymous contribution greater than $10, the committee may retain $10 and then shall donate the excess to a charity of the committee’s choosing or to the Wisconsin Common School Fund (Wis. Stat. § 11.1108). Acceptance of the contribution and donation of the excess should be reported on the committee’s next report. A conduit may not accept anonymous contributions (Wis. Stat. § 11.0101(7)).
A committee or conduit may not accept a cash contribution exceeding $100. Any contribution greater than $100 shall be made by negotiable instrument, such as a check (Wis. Stat. § 11.1107).

References: § 11
 § 11
 § 30121
 § 13
 § 13
 § 13
 § 13
 § 13
 § 11
 § 11
 § 11