MSOSX — MainStay MacKay Common Stock Fund
Data updated: 2026-09-23
MSOSX — MainStay MacKay Common Stock Fund. United States Mid Cap Blend / Core Equity · $341.07M AUM. Holdings, fees, performance and SEC filings.
MSOSX Fund Overview
MSOSX — MainStay MacKay Common Stock Fund is a US mutual fund managed by New York Life Investments Funds, categorised as United States Mid Cap Blend / Core Equity. 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: United States Mid Cap Blend / Core Equity
- Assets under management: $341.07M
- 1-year return: 11.9%
- Ticker: MSOSX
- SEC CIK: 0000787441
- SEC series ID: S000006903
- Share class ID: C000166837
MSOSX Investment Objective and Strategy
MainStay MacKay Common Stock 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 long-term growth of capital.
Principal investment strategy
"The Fund normally invests at least 80% of its assets (net assets plus any borrowings for investment purposes) in common stocks. The Fund primarily invests in common stocks of U.S. companies with market capitalizations that, at the time of investment, are similar to companies in the Standard & Poor's 500 Index (""S&P 500 Index) (which ranged from $3.4 billion to $867.5 billion as of December 31, 2017) and the Russell 1000 Index (which ranged from $653.7 million to $867.5 billion as of December 31, 2017). Investment Process: Using an objective, disciplined and broadly-applied process, MacKay Shields LLC, the Fund's Subadvisor, selects securities that it believes have the most potential to appreciate, while seeking to limit exposure to risk. The Subadvisor also seeks to control the Fund's exposure to risk by seeking to construct a broadly-diversified portfolio of securities issued by a large number of companies, across sectors and industries using quantitative analysis to identify undervalued and overvalued securities.
The Subadvisor uses a quantitative model that is designed to evaluate individual issuers and securities across multiple criteria, including valuation, momentum and market sentiment. The Subadvisor also conducts a qualitative review of the results of the quantitative analysis. In certain cases, the Subadvisor may deviate from positions or weightings suggested by the quantitative analysis to account for events and conditions that may not be quantifiable by the analysis, such as company-specific and market events. The Subadvisor evaluates the quantitative model and, from time to time, the Subadvisor may adjust the metrics and data underlying its quantitative analysis or model for a variety reasons, including, without limitation, to account for changing market, financial or economic conditions.
The Subadvisor may sell a security if, among other reasons, it no longer believes the security will contribute to meeting the investment objective of the Fund, if better opportunities are identified, or if it determines the initial investment expectations are not being met."
MSOSX Holdings
Top 10 holdings of MainStay MacKay Common Stock Fund by percentage of net assets, from the fund's latest SEC N-PORT filing.
| Holding | % of net assets |
|---|---|
| PACCAR, Inc. | 5.79% |
| M&T Bank Corp. | 5.59% |
| Constellation Software, Inc. | 5.49% |
| Credit Acceptance Corp. | 5.08% |
| Progressive Corp. (The) | 4.87% |
| Cintas Corp. | 4.75% |
| Expeditors International of Washington, Inc. | 4.74% |
| Amphenol Corp. | 4.65% |
| NVR, Inc. | 4.55% |
| Linde plc | 4.53% |
MSOSX Portfolio Allocation
Asset-class allocation of MainStay MacKay Common Stock Fund by percentage of net assets, from the latest SEC N-PORT filing.
| Asset class | Allocation |
|---|---|
| Equity | 99.2% |
| Cash & Equivalents | 1.0% |
MSOSX Performance
Total returns for MSOSX (as of 2026-10-01), from SEC filings.
| Period | Total return |
|---|---|
| 1 year | 11.9% |
| 3 years (annualised) | 11.2% |
MSOSX Risk Information
Risk metrics for MSOSX, derived from monthly returns in SEC filings.
- 1-year volatility (annualised): 16.0%
MSOSX Costs and Fees
MSOSX costs about $130 per $10,000 invested per year in fund expenses.
- Net expense ratio: 1.30%
- Gross expense ratio: 1.30%
- Portfolio turnover: 15%
- Brokerage commissions: 0.35 bps of average net assets (SEC N-CEN)
MSOSX Cashflows
Over the 12 months to 2026-04, MainStay MacKay Common Stock Fund had net outflows of $117.64M, from monthly SEC N-PORT filings.
| Month | Net flow |
|---|---|
| 2026-04 | −$11.27M |
| 2026-03 | −$21.67M |
| 2026-02 | −$39.03M |
| 2026-01 | −$60.86M |
| 2025-12 | $5.63M |
| 2025-11 | −$10.41M |
MSOSX Debt Constituents
No individual debt constituents are reported in MainStay MacKay Common Stock Fund's latest SEC N-PORT filing.
MSOSX Prospectus and SEC Filings
Official MainStay MacKay Common Stock 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 United States Mid Cap Blend / Core Equity funds tracked on ABC INVEST:
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.