MSIRX — MainStay MacKay Unconstrained Bond Fund

MSIRX Fund Overview

MSIRX — MainStay MacKay Unconstrained Bond Fund is a US mutual fund managed by New York Life Investments Funds, categorised as Intermediate Total / Aggregate Bond. ABC INVEST provides holdings, performance, costs, cashflows, risk data, prospectus documents and SEC filings, sourced from SEC filings.

• Type: US mutual fund
• Manager: New York Life Investments Funds
• Category: Intermediate Total / Aggregate Bond
• Assets under management: $1.79B
• 1-year return: 6.7%
• Ticker: MSIRX
• SEC CIK: 0000787441
• SEC series ID: S000006894
• Share class ID: C000138226

MSIRX Investment Objective and Strategy

MainStay MacKay Unconstrained Bond Fund describes its objective and strategy as follows, from its latest prospectus filed with the SEC by New York Life Investments Funds.

Investment objective

The Fund seeks total return by investing primarily in domestic and foreign debt securities.

Principal investment strategy

The Fund seeks to achieve its investment objective through a flexible investment process that allocates investments across the global fixed-income markets. The Fund, under normal circumstances, invests at least 80% of its assets (net assets plus any borrowings for investment purposes) in a diversified portfolio of debt or debt-related securities such as: debt or debt-related securities issued or guaranteed by the U.S. or foreign governments, their agencies or instrumentalities; obligations of international or supranational entities; debt or debt-related securities issued by U.S. or foreign corporate entities; zero coupon bonds; municipal bonds; mortgage-related and other asset-backed securities; loan participation interests; convertible bonds; and variable or floating rate debt securities.

The Fund may invest in debt securities that are rated investment grade and below investment grade by an independent rating agency. Securities that are rated below investment grade by independent rating agencies are commonly referred to as high-yield securities or junk bonds. If independent rating agencies assign different ratings to the same security, the Fund will use the lower rating for purposes of determining the security's credit quality. The securities may be denominated in U.S. or foreign currencies, and may have fixed, variable, floating or inverse floating rates of interest. The Fund may invest without limitation in securities of foreign issuers, including emerging markets. The currency exposure of non-U.S. investments may or may not be hedged. The Fund may invest up to 15% of its net assets in equity securities.

The Fund intends to utilize various investment strategies in a broad array of fixed-income sectors to achieve its investment objective. The Fund will not be constrained by portfolio management relative to an index. Because an unconstrained bond portfolio does not track a fixed-income index, its performance may vary at times and demonstrate low correlation to traditional fixed-income indices. In pursuing its investment objective, the Fund's investment strategy is subject to market risk and shares may gain or lose value. The average portfolio duration of the Fund will normally vary from 0 to 7 years. Duration is a measure used to determine the sensitivity of a security's price to changes in interest rates. The longer a security's duration, the more sensitive it will be to changes in interest rates.

The Fund may invest in derivatives, such as futures, options, forward commitments and interest rate swap agreements to try to enhance returns or reduce the risk of loss by hedging certain of its holdings or manage duration. The Fund may invest up to 25% of its total assets in swaps. The Fund may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Fund's short positions, either direct short positions or through credit default swaps or total return swaps, may total up to 20% of the Fund's net assets. The Fund may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls).

Investment Process: MacKay Shields LLC, the Fund's Subadvisor, seeks to identify investment opportunities through an investment process focused on macroeconomic analysis and bottom-up security selection. The Subadvisor allocates the Fund's investments among the various bond market sectors based on current and projected economic and market conditions. The Fund may invest across bond market sectors, geographies and credit qualities. The Subadvisor may sell a security if it no longer believes the security will contribute to meeting the investment objective of the Fund. In considering whether to sell a security, the Subadvisor may evaluate, among other things, the condition of the domestic and foreign economies, and meaningful changes in the issuer's financial condition, including changes in the issuer's credit risk and competitiveness.

MSIRX Holdings

Top 10 holdings of MainStay MacKay Unconstrained Bond Fund by percentage of net assets, from the fund's latest SEC N-PORT filing.

View all MSIRX holdings

MSIRX Portfolio Allocation

Asset-class allocation of MainStay MacKay Unconstrained Bond Fund by percentage of net assets, from the latest SEC N-PORT filing.

MSIRX Performance

Total returns for MSIRX (as of 2026-10-01), from SEC filings.

MSIRX Risk Information

Risk metrics for MSIRX, derived from monthly returns in SEC filings.

• 1-year volatility (annualised): 5.5%

MSIRX Costs and Fees

MSIRX costs about $113 per $10,000 invested per year in fund expenses.

• Net expense ratio: 1.13%
• Gross expense ratio: 1.13%
• Portfolio turnover: 136%
• Brokerage commissions: 0.71 bps of average net assets (SEC N-CEN)

MSIRX Cashflows

Over the 12 months to 2026-04, MainStay MacKay Unconstrained Bond Fund had net inflows of $756.01M, from monthly SEC N-PORT filings.

MSIRX Debt Constituents

Largest debt holdings of MainStay MacKay Unconstrained Bond Fund by percentage of net assets, from the latest SEC N-PORT filing.

MSIRX Prospectus and SEC Filings

Official MainStay MacKay Unconstrained Bond Fund filings on SEC EDGAR — prospectus, portfolio holdings and annual reports.

• Prospectus (485BPOS) — filed 2026-02-26
• Prospectus (485BPOS) — filed 2025-02-25
• Prospectus supplement (497) — filed 2025-02-28
• Portfolio holdings (N-PORT) — filed 2026-09-23
• Portfolio holdings (N-PORT) — filed 2026-06-25
• Portfolio holdings (N-PORT) — filed 2026-03-26
• Annual census (N-CEN) — filed 2026-01-13
• Annual census (N-CEN) — filed 2025-01-13

Related Funds

Other Intermediate Total / Aggregate Bond funds tracked on ABC INVEST:

• Vanguard Total Bond Market Index Fund (VBMFX)
• Vanguard Total Bond Market II Index Fund (VTBIX)
• Vanguard Total International Bond II Index Fund (VTIIX)
• iShares Core U.S. Aggregate Bond ETF (AGG)
• Vanguard Total International Bond Index Fund (VTIBX)

Data Sources

ABC INVEST compiles this page from public filings made to the U.S. Securities and Exchange Commission (SEC) through EDGAR: portfolio holdings and monthly cashflows from Form N-PORT, expenses and returns from fund prospectuses (Form 485BPOS) and the SEC DERA Risk/Return Summary data sets, annual data from Form N-CEN, and shareholder reports from Form N-CSR.