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 135% of the average value of its portfolio.

Principal Investment Strategies

The Portfolio invests primarily in common stocks of large capitalization U.S. growth companies. Under normal circumstances, the Portfolio invests at least 80% of its net assets (plus borrowings for investment purposes, if any) in stocks of large capitalization companies (that is, those with market capitalizations at the time of investment that are within the range of market capitalizations of the companies in the Russell 1000^® Growth Index for the previous 12 months). As of March 31, 2023, the capitalization range of the Russell 1000^® Growth Index was between $597.18 million and $2.61 trillion. From time to time the Portfolio may also have substantial positions in securities of foreign companies. In addition, from time to time the Portfolio may also have substantial positions in a particular sector of the economy. 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.

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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.

The Portfolio may engage in active and frequent trading of portfolio securities to achieve its primary investment strategies.

The Portfolio may use derivatives to hedge its portfolio against market and currency risks or to gain exposure to equity markets. The Portfolio may also use derivatives to hedge its investment portfolio against interest rate risks or to seek to enhance its return. Derivatives are financial instruments whose value is derived from another security, a commodity, a currency or an index. The derivatives that the Portfolio intends to use are futures contracts, which may include financial and currency futures, and options on such futures.

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.

Derivatives Risk — Derivatives can be highly volatile and involve risks in addition to the risks of the underlying referenced securities. Using derivatives can increase fund losses and reduce opportunities for gains when market prices, interest rates or the derivative instruments themselves behave in a way not anticipated by the Portfolio. Derivatives may be difficult to sell, unwind or value, and the counterparty may default on its obligations to the Portfolio. Changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index and the Portfolio could lose more than the principal amount invested. In addition to investing in derivatives to implement its strategy, the Portfolio may also use derivative instruments for hedging purposes, in an attempt to reduce the risk of loss from falling stock prices or lower foreign currency valuations, increased interest rates or other adverse market developments. There can be no assurance that a hedging technique will work as intended. Portfolio performance may be diminished by the added cost of the derivative instruments.

Growth Strategy Risk — Growth stocks may be more volatile than other stocks because they are generally more sensitive to investor perceptions of the issuing company’s growth of earnings potential. Also, since growth companies usually invest a high portion of earnings in their business, growth stocks may lack the dividends of value stocks that can cushion stock prices in a falling market.

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.

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.

Sector Risk — A certain sector may not perform as well as companies in other sectors or the market as a whole. When the Portfolio concentrates its investments in a sector, it is more susceptible to any adverse economic, business or other developments generally affecting companies in that sector.

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Foreign Investments Risk — Foreign investments involve risks not normally encountered with domestic securities. These include political, regulatory and economic instability in some countries, the imposition of economic sanctions, changes in currency rates and market inefficiencies. The laws of some foreign countries may limit the Portfolio’s ability to invest in securities of certain issuers organized under the laws of those countries. Trade tensions and economic sanctions on individuals and companies can contribute to market volatility. This may adversely impact the Portfolio’s performance.

Emerging Markets Risk — Securities issued or traded in emerging markets generally entail greater risks than securities issued or traded in developed markets. Emerging market countries may have relatively unstable governments and may present the risk of nationalization of business, expropriation, confiscatory taxation or, in certain instances, reversion to closed market, centrally planned economies. Differences in regulatory, accounting, auditing and financial reporting and recordkeeping standards could impede the ability to evaluate local companies or impact the Portfolio’s performance. The typically small size of the markets of securities of issuers located in emerging markets and the possibility of a low or nonexistent volume of trading in those securities may also result in a lack of liquidity and in price volatility of those securities.

High Portfolio Turnover Risk — Portfolios with high portfolio turnover rates will incur higher transactions expenses, thereby decreasing overall return. In addition, there is a possibility that a portfolio with a high turnover rate will sell some securities before their market values reach full potential.

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 and a secondary 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 2007 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.

During the period shown in the bar chart, the Portfolio’s highest return for a quarter was 26.61%. That was the quarter ended on June 30, 2020. The lowest return for a quarter was -21.83%. 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.

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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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