Investment Objective

Seeks long-term growth of capital.

Fees and Expenses of the Portfolio

This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Portfolio. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and example below. The table does not reflect fees or expenses that may be charged in connection with variable annuities and variable life insurance policies issued by the insurance companies which offer the Portfolio as an underlying investment option. If such charges were included, the following fees and expenses would be higher.

Shareholder Fees (fees paid directly from your investment): —

Example. This Example is intended to help you compare the cost of investing your variable contract assets in the Portfolio with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. The costs indicated below do not reflect the additional expenses of variable contracts. These costs would be higher if variable contract charges were added. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Portfolio Turnover. The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 90% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the Portfolio invests at least 80% of its net assets (plus borrowings for investment purposes, if any) in common stocks of the 1,000 largest publicly traded U.S. companies. As of March 31, 2023, those companies had market capitalizations ranging between $542.82 million and $2.61 trillion.

The Portfolio is actively managed by BlackRock Investment Management, LLC (“BlackRock”) under a sub-advisory agreement with the Adviser. BlackRock began managing the Portfolio in February 2019. BlackRock seeks to pursue the Portfolio’s investment objective by investing in large cap securities in a disciplined manner, by using proprietary return forecast models that incorporate quantitative analysis. These forecast models are designed to identify aspects of mispricing across stocks that the Portfolio can seek to capture by over- and under-weighting particular equities while seeking to control incremental risk. BlackRock then constructs and rebalances the Portfolio by integrating its investment insights with the model-based optimization process. BlackRock has no stated minimum holding period for investments and may buy or sell securities whenever it sees an appropriate opportunity.

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The portfolio managers consider a variety of factors in determining whether to sell a security, including changes in market conditions, changes in prospects for the security, alternative investment possibilities and other factors they believe to be relevant.

Principal Risks

There is no assurance that the Portfolio will meet its investment objective. The value of your investment in the Portfolio and the amount of the return you receive on your investment may fluctuate significantly. You could lose money, or have less return than the market in general, by investing in the Portfolio. The principal risks of investing in the Portfolio are:

Market Risk — A security’s price may change in response to changes in conditions in securities markets in general. Markets tend to move in cycles with periods of rising prices and periods of falling prices. They can decline for many reasons, including adverse political or economic developments domestically or abroad, changes in investor psychology, or heavy institutional selling. In the case of debt securities, changes in the overall level of interest rates affect the security’s price. Different types of stocks sometimes shift into and out of favor with investors. For example, at times the market may not favor growth-oriented stocks. Instead, it might favor value stocks or not favor stocks at all. If the Portfolio focuses on a particular investment style, its performance will sometimes be better or worse than the performance of funds focusing on other types of investments. A significant national or international event, natural disaster or widespread health crisis, such as the COVID-19 global pandemic, could cause substantial market volatility, exchange trading suspensions and closures, severe market dislocations and liquidity constraints, impact the ability to complete redemptions, and affect the Portfolio’s performance.

Issuer Risk — The value of a security may decline for reasons related to the issuer, such as earnings stability, overall financial soundness, management performance and reduced demand for the issuer’s goods or services.

Large-Cap Company Risk — Larger more established companies may be unable to respond quickly to new competitive challenges such as changes in technology and consumer tastes. Many larger companies also may not be able to attain the high growth rate of successful smaller companies, especially during extended periods of economic expansion.

Performance

The accompanying bar chart and table provide some indication of the risks of investing in the Portfolio. They show changes in the Portfolio’s performance for each of the last ten years and the Portfolio’s average annual returns for the last one year, five years and ten years compared to those of a broad-based securities market index. The Portfolio’s past performance does not necessarily indicate how it will perform in the future. Variable contract charges are not reflected in the chart or table. If they were, the returns would be less than those shown.

BlackRock began sub-advising the Portfolio under its current strategy on February 1, 2019. From May 2002 through January 31, 2019, the Portfolio was sub-advised by Suffolk Capital Management, LLC using a different strategy. Performance returns shown below for periods prior to February 1, 2019 are not indicative of returns of the current strategy or sub-adviser.

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During the period shown in the bar chart, the Portfolio’s highest return for a quarter was 20.45%. That was the quarter ended on June 30, 2020. The lowest return for a quarter was -21.95%. That was the quarter ended on December 31, 2018. To obtain performance information up to the most recent month end, call toll free 877.781.6392.

Management

Ohio National Investments, Inc. serves as the investment adviser for the Portfolio. BlackRock serves as the investment sub-adviser for the Portfolio. BlackRock has been a sub-adviser for the Portfolio since February 1, 2019. Raffaele Savi, a Managing Director of BlackRock, and Travis Cooke, CFA, also a Managing Director of BlackRock, have been portfolio managers of the Portfolio since February 2019.

Purchase and Sale of Fund Shares

Shares of the Portfolio are offered only to separate accounts of insurance companies, which use the Portfolio shares as an underlying investment for variable annuities and variable life insurance contracts, and to portfolios of the Fund in connection with ONLIC, ONLAC and National Security’s variable annuity contracts and variable life insurance policies. You may select funds and make transfers among fund options as described in your variable contract prospectus. The separate accounts of the insurance companies may purchase and redeem Portfolio shares, at their net asset value next computed, each day the New York Stock Exchange is open for unrestricted trading. Please read your variable contract prospectus for more information about your variable contract.

Tax Information

The tax treatment of payments made from a variable contract is described in the contract’s prospectus. Generally, contract owners are not taxed on income or gains realized within their contract until they receive payments from the contract.

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