B-1 STATEMENT OF ADDITIONAL INFORMATION Dated May 1 ...

and cost of trade execution of Portfolio transactions. The Portfolios have received assurances fromAmerican Century Investment Management, Inc. and Capital Guardian Trust Company that these vendorsare subject to a duty of confidentiality.Regulators and Other Required Disclosures. Holdings data may be disclosed to regulators andexchanges at the request or as otherwise required by the foregoing, and may also be disclosed to thirdparties in circumstances required by law, rule or regulation or court order or subpoena.Investment Professionals. Holdings data may be disclosed on an ongoing basis (generally updatedmonthly within one week of month-end) to certain investment professionals (“Investment Professionals”)solely for the purpose of permitting the selected professionals to consider and propose investment ideasand trading strategies that may benefit the Portfolios. Holdings data of the Portfolios is disclosed on anaggregated basis. No data on a Portfolio-by-Portfolio basis is disclosed. Access to such data is limited tothose Investment Professionals that (1) have been approved by an officer of the Fund, and (2) haveentered into confidentiality agreements limiting their use of such data to the foregoing purposes andrequiring them to keep the data confidential and stipulating that the data may not be used under anycircumstances for the basis of trading. The list of approved Investment Professionals as of December 31,2008 is included in Appendix G.Securities Lending Parties. Holdings data may be disclosed on an ongoing basis (generally updateddaily) to certain securities lending agents and borrowers (“Lending Parties”) pursuant to securities lendingprograms utilized on a Portfolio’s behalf. Holdings data of the Portfolios is disclosed on an aggregatedbasis. No data on a Portfolio-by-Portfolio basis is disclosed. Access to such data is limited to thoseLending Parties that (1) have been approved by an officer of the Fund, and (2) have entered intoconfidentiality agreements limiting their use of such data to the operation of the securities lendingprograms and requiring them to keep the data confidential. The list of approved Lending Parties as ofDecember 31, 2008 is included in Appendix G.Northwestern Mutual Separate Accounts. Holdings data may be disclosed to the NorthwesternMutual variable life insurance and variable annuity separate accounts that invest in shares of thePortfolios. Holdings data may also be disclosed to Northwestern Mutual and Northwestern MutualInvestment Services, LLC in their capacities as co-depositors for the Northwestern Mutual separateaccounts.Other. Material holdings information may be disclosed in other circumstances prior to the publicavailability of such data only upon the approval of both the Fund’s chief compliance officer and anotherFund officer, which approval will be based on compliance with the Holdings Disclosure Policy andProcedures, including obtaining from the recipient, where appropriate, a confidentiality agreementlimiting their use of such data, requiring them to keep the data confidential, and stipulating that the datamay not be used under any circumstances for the basis of trading.Parties receiving non-public holdings data from the Fund or its investment advisers will be requiredto keep such data confidential in accordance with the Holdings Disclosure Policies and Procedurespursuant to confidentiality provisions in their service contracts, specific confidentiality agreements, dutiesof trust and confidence owed to the Fund (e.g., legal counsel) and/or specific directives from the Fund.Monitoring ProceduresThe Holdings Disclosure Policy and Procedures require the Fund’s chief compliance officer to:(i) monitor the disclosure and use of portfolio holdings information; (ii) report at least annually to theFund’s Directors on their operation and any material changes to them; (iii) inform the Fund’s serviceproviders as to the Holdings Disclosure Policy and Procedures; and (iv) review, or cause to be reviewed,at least annually the lists of Investment Professionals and Lending Parties with access to portfolioholdings.B-60