Periodic/Interim Report by Investment Company (Form N-30B-2)

Adams Diversified Equity Fund, Inc. (the "Fund") employs a Managed Distribution Policy ("MDP") to enhance long-term shareholder value by paying level quarterly distributions at a committed rate of 8% of average net asset value ("NAV") per year. The Fund pays distributions four times a year. Distributions under the MDP can be derived from net investment income, realized capital gains, or possibly, returns of capital, and are payable in newly issued shares of common stock unless a shareholder specifically elects to receive cash. The Fund has committed to distribute 2% of average NAV for each quarterly distribution, with the fourth quarter distribution to be the greater of 2% of average NAV or the amount needed to satisfy minimum distribution requirements of the Internal Revenue Code for regulated investment companies. Average NAV is based on the average of the previous four quarter-end NAVs per share prior to each declaration date.

With each distribution, the Fund will issue a notice to shareholders that will provide detailed information regarding the amount and composition of the distribution and other related information. The amounts and sources of distributions reported in the notice to shareholders are only estimates and are not being provided for tax reporting purposes. The actual amounts and sources of the distributions for tax reporting purposes will depend upon the Fund's investment experience during its fiscal year and may be subject to changes based on tax regulations. Shareholders will receive a Form 1099-DIV in January for the previous calendar year that will indicate how to report these distributions for federal income tax purposes.

​

Disclaimers

The primary purpose of the MDP is to provide shareholders with a consistent, but not guaranteed, rate of distribution each quarter. You should not draw any conclusions about the Fund's investment performance from the amount of the current distribution or from the terms of the Fund's MDP. The Board may amend or terminate the MDP at any time without prior notice to shareholders. However, at this time, there are no reasonably foreseeable circumstances that might cause the termination of the MDP.

Dear Fellow Shareholders,

U.S. equities continued to move higher in the third quarter driven by robust corporate earnings, positive earnings revisions, and ongoing high levels of artificial intelligence (AI)-related investment-Goldman Sachs estimates that global AI investment in data centers, semiconductors, and other infrastructure will exceed $1 trillion in 2026. These positive factors overcame investors' worries about persistent inflation, elevated interest rates, and geopolitical uncertainty.

Market leadership shifted considerably during the quarter. Many stocks that were strong in the first half of the year experienced weakness, while numerous underperformers rebounded. These moves narrowed some of the wide performance disparities that had developed earlier in the year, without fundamentally reversing the market's prevailing trends.

Reported second quarter earnings for the S&P 500 Index were more than 50% higher than a year earlier, the strongest growth since the pandemic-era rebound of 2021. The strength was broad based, with nine of the Index's 11 sectors posting double-digit earnings growth. Third quarter earnings estimates also continued to move higher.

Inflation eased from its May peak but stubbornly remained above the U.S. Federal Reserve's (Fed) target. The ongoing conflict with Iran continued to disrupt global energy markets and put upward pressure on energy prices. The outlook for interest rates also continued to shift. In a marked reversal from the end of 2025, when the Fed and investors anticipated 2026 rate cuts, the Fed raised rates in September for the first time since 2023, citing persistent inflation amidst continued economic strength. Policymakers and the markets ended the quarter expecting additional tightening through the end of this year and into 2027.

Long-term U.S. Treasury rates moved higher, with the 10-year yield climbing above 5% amid concerns around inflation, the federal fiscal outlook, and heavy debt issuance. The prospect of higher interest rates, which tend to raise borrowing costs and pressure equity valuations, has become an important part of the investment backdrop amid heavy federal borrowing that is increasingly competing with the financing needs associated with the AI investment boom.

The S&P 500 Index's total return for the quarter was 2.3%, resulting in a 12.8% year-to-date advance. Energy, which advanced 17.2%, was the top-performing sector in the third quarter, supported by continued concerns about global supply disruptions stemming from the conflict in the Middle East. Information Technology (IT), Health Care, and Communication Services also outperformed. In contrast,

the seven remaining sectors in the S&P 500 experienced negative returns in the quarter. The Utilities sector struggled amid rising interest rates and was the worst performing sector, declining 12.4%.

Our Fund advanced 1.9% in the third quarter, modestly trailing the benchmark. The IT and Materials sectors were the biggest positive contributors to our relative performance while the Health Care and Industrials sectors were the largest detractors. The two lagging sectors were the best relative performers for the first half of the year, reflecting the reversal in some stock performance noted previously.

IT was the leading contributor to the Fund's relative performance in the quarter with a return of 8.6% compared to the benchmark's 7.2% advance. Several of our software holdings benefited as earlier concerns about widespread AI disruption began to ease. Notably, Microsoft increased 37.8% in the quarter on strong earnings that showcased broad-based revenue growth and positive operating leverage related to its AI investment. Additionally, the Fund's return benefited from increased demand for cybersecurity and data management software integral to the evolution of AI through our holdings in Palo Alto Networks and Snowflake, respectively.

In Materials, the Fund generated a 2.6% return compared to the benchmark's -2.8% return. Our position in Freeport-McMoran was a source of relative strength. As one of the world's largest copper miners, the company benefited from steady strength in copper prices, which achieved a 20-year high in September. The company's continued progress to restore production from its Grasberg mine in Indonesia also provided market support for the stock.

Our Industrials holdings returned -13.2%, compared with -9.8% for the benchmark. Some of the Fund's AI-infrastructure beneficiaries reversed trend in the quarter. GE Vernova, an energy equipment manufacturer, was down 19.2% and Vertiv Holdings, a provider of cooling technology, was down 27.9%, despite reporting strong earnings and backlogs. For the year to date, the stocks were up 45.7% and 38.3%, respectively. We continue to see growth opportunities for both supported by a favorable spending and demand environment.

Health Care, the biggest contributor to our first half results, generated a 2.3% return, underperforming the Index's return of 6.5%. Our holdings in managed care stocks, notably CVS Health and UnitedHealth Group, declined 16.7% and 11.2%, respectively, on growth concerns related to their pharmacy benefits management businesses, which are relatively small pieces of each company but face regulatory and pricing pressures. Despite this, both companies reported strong earnings driven by pricing gains and improving medical cost trends, the dynamics that we see as the long-term drivers for these stocks.

For the nine months ended September 30, 2026, the total return on the Fund's net asset value (NAV) per share (with dividends and capital gains reinvested) was 12.9%. This compares to a 12.8% total return for the S&P 500 and a 11.5% total return for the Morningstar U.S. Large Blend category over the same time period. The total return on the market price of the Fund's shares for the period was 16.6%. During the first nine months of this year, the Fund paid distributions to shareholders in the amount of $179.5 million, or $1.45 per share.

For the twelve months ended September 30, 2026, the Fund's total return on NAV was 15.6%. Comparable figures for the S&P 500 and the Morningstar U.S. Large Blend category were 15.7% and 14.1%, respectively. The Fund's total return on market price for the period was 24.4%.

This market has been remarkably resilient through a range of challenges. November's elections add another source of uncertainty, particularly around the direction of economic and fiscal policy. Rising debt levels and stubborn inflation could eventually weigh more heavily on economic activity and financial markets. As we've seen, though, even significant challenges and rapid changes in the economic backdrop do not affect every company equally.

Shifting market and sector leadership, interest rate expectations, and commodity prices, along with the broader policy and geopolitical backdrop that we've seen in 2026, reinforce the importance of a disciplined investment approach. Short-term events can change stock prices and market leadership without necessarily changing the long-term investment case. As some of the wide gaps between market leaders and laggards narrowed, we believe the market has become somewhat more balanced, creating a better environment for fundamental stock selection. As always, we will continue to focus on companies with attractive long-term opportunities while managing risks that can cut across traditional sector and industry lines.

We believe distinguishing between developments that may alter a company's long-term prospects and those that can primarily affect near-term sentiment is an important part of successful investing. That discipline helps us look beyond short-term volatility, remain measured in how we take risk, and stay focused on positioning the portfolio to participate in long-term opportunities.

By order of the Board of Directors,

October 15, 2026

​

Disclaimers​

This report contains "forward-looking statements" within the meaning of the Securities Act of 1933 and the Securities Exchange Act of 1934. By their nature, all forward-looking statements involve risks and uncertainties, and actual results could differ materially from those contemplated by the forward-looking statements. Several factors that could materially affect the Fund's actual results are the performance of the portfolio of stocks held by the Fund, the conditions in the U.S. and international financial markets, the price at which shares of the Fund will trade in the public markets, and other factors discussed in the Fund's periodic filings with the Securities and Exchange Commission.​

This report is transmitted to the shareholders of the Fund for their information. It is not a prospectus, circular or representation intended for use in the purchase or sale of shares of the Fund or of any securities mentioned in the report. The rates of return will vary and the principal value of an investment will fluctuate. Shares, if sold, may be worth more or less than their original cost. Past performance is no guarantee of future investment results.

​

*

Annualized

​

Ten Largest Equity Portfolio Holdings

​

September 30, 2026

(unaudited)

​

*

Non-controlled affiliated closed-end fund

​

​

(a)

Common stocks are listed on the New York Stock Exchange or NASDAQ and are valued at the last reported sale price on the day of valuation.​

​

(b)

Presently non-dividend paying.

​

(c)

Non-controlled affiliate, a closed-end sector fund, registered as an investment company under the Investment Company Act of 1940.

​

(d)

Controlled affiliate valued using fair value procedures.

​

(e)

Rate presented is as of period-end and represents the annualized yield earned over the previous seven days.​

​

(f)

During the nine months ended September 30, 2026, investments in affiliates were as follows:

​

​

*

The Fund elected to receive 152,718 shares (cost basis $4,067,648) in lieu of cash for distributions received in 2026. Cost basis at end of period was $46,496,561.

​

Information regarding transactions in equity securities during the quarter can be found on our website at: www.adamsfunds.com.​

Adams Diversified Equity Fund, Inc.

​

Board of Directors

​

(1)

Member of Executive Committee

​

(2)

Member of Audit Committee

​

(3)

Member of Compensation Committee

​

(4)

Member of Nominating and Governance Committee

​

(5)

Chair of the Board

​

Officers

​

500 East Pratt Street, Suite 1300, Baltimore, MD 21202

410.752.5900 800.638.2479

Website: www.adamsfunds.com

Tickers: ADX (NYSE), XADEX (NASDAQ)

Independent Registered Public Accounting Firm: PricewaterhouseCoopers LLP

Custodian of Securities: The Northern Trust Company

Transfer Agent & Registrar: Computershare Trust Company, N.A.

P.O. Box 43078
Providence, RI 02940-3078
(877) 260-8188
Website: www.computershare.com/us
Email: [email protected]