Shareholder Protection Act of 2010

Requires institutional investment managers to disclose annually in mandatory reports how they voted on corporate political expenditures. Requires the Securities and Exchange Commission (SEC) to promulgate regulations requiring: (1) investment managers to report how they voted within 30 days after the vote; and (2) the report to be made available to the public through the EDGAR system.

Prohibits any person from bringing any civil, criminal, or administrative action against an institutional investment manager, or any of its employees, officers, or directors, based solely upon the investment manager's decision to either divest from, or not to invest in, the securities of an issuer based upon political expenditures made by that issuer. Applies this prohibition only to an institutional investment manager, or its employees, officers, or directors, that makes such disclosures in accordance with SEC regulations.

(Sec. 4) Requires the SEC to direct the national securities exchanges and national securities associations to prohibit the listing of any class of equity security of an issuer whose corporate bylaws do not expressly provide for a vote by its board of directors on any individual expenditure: (1) for political activities in excess of $50,000; or (2) that makes the total expenditures by the issuer for a particular election $50,000 or more. Requires an issuer to make the individual votes of the directors regarding any such expenditure publicly available within 48 hours.

(Sec. 5) Directs the SEC to: (1) require issuers to disclose expenditures for political activities made during the preceding quarter, along with specified details, and the individual votes by board members authorizing such expenditures; (2) make such reports publicly available on its SEC website and through the EDGAR system; and (3) require each issuer to include in its annual report to shareholders a summary of all expenditures for political activities made during the preceding year in excess of $10,000.

Directs the SEC to require each issuer to: (1) obtain and disclose in its mandatory reports any materials created with or purchased by any expenditure for political activities; and (2) disclose such materials in a clear and conspicuous location on its Internet website within 48 hours of obtaining the materials.

(Sec. 6) Directs the SEC to assess and report to Congress annually on the compliance of public corporations and their management with the requirements of this Act. Requires the Comptroller General to evaluate and report periodically to Congress on the effectiveness of the SEC's oversight of its reporting and disclosure requirements.