Insiders across multiple public companies registered meaningful transactions in filings covering late August 2026. The disclosures show an array of purchases by company directors and concentrated sales by senior executives and large shareholders. Below we summarize the most substantial transactions disclosed for Thursday, August 27, 2026, and provide context drawn from the filings.
Summary of the largest purchases
Several directors increased their holdings during the period, with transactions recorded in energy storage, consumer packaged goods, real estate investment trusts and other sectors.
- Energy Vault Holdings, Inc. (NASDAQ: NRGV) - Director Dylan Hixon acquired 27,472 shares of common stock on August 17, 2026, at a per-share price of $3.878, for a total outlay of $106,536. The filing notes the shares were purchased indirectly and are held in the Dylan Hixon Childrens Trust FBO Casimir R. Hixon, of which Mr. Hixon is the sole trustee. The company’s shares were trading at $3.75 at the time the report referenced; the filing notes a 97% gain for the stock over the prior 12 months. InvestingPro analysis cited in the disclosure characterizes NRGV as appearing slightly overvalued relative to its Fair Value estimate. The 27,472 shares are included in Mr. Hixon’s reported beneficial ownership following the transaction.
- Keurig Dr Pepper Inc. (NASDAQ: KDP) - Director Aaron E. Alt purchased 7,862 shares of common stock on August 25, 2026. The trades were executed at prices ranging from $31.83 to $31.84 per share, producing a weighted average purchase price of $31.83 and a total reported cost of $250,247. The filing notes that KDP stock traded at $31.87 at the time referenced, delivering a 16.6% year-to-date gain and a market capitalization of $43.83 billion. InvestingPro analysis included in the disclosure indicates the stock appears undervalued at current levels. The filing also documents the company’s historic dividend increases, noting five consecutive annual raises and a current yield of 2.89 percent.
- Welltower Inc. (NASDAQ: WELL) - Director Andrew Gundlach purchased a total of 10,000 shares for aggregate consideration of $2,407,650 across two days in late August 2026. On August 25, 2026, Mr. Gundlach acquired 5,000 shares indirectly through two separate trusts - 2,500 shares for the ELLEN-MARIA GORRISSEN TRUST I and 2,500 for the ELLEN-MARIA GORRISSEN TRUST II - at a weighted average price of $239.47, with individual trades ranging from $239.27 to $239.50. The filings indicate the weighted average price for the broader set of purchases ranged from $239.47 to $242.06 per share. The disclosure notes WELL trading near a 52-week high of $255.20 and delivering a 46% return over the past year.
- American Assets Trust, Inc. (NYSE: AAT) - Ernest S. Rady, who serves as Executive Chairman, Director and a 10% owner, reported purchases totaling 79,729 shares during two late-August transactions. On August 24, 2026, Mr. Rady acquired 29,729 shares at $22.74 per share and on August 26, 2026 he purchased an additional 50,000 shares at $22.89 per share. The combined purchases are reported to total approximately $1.82 million. The filing observes that AAT’s stock has returned 24% year-to-date and is trading below InvestingPro Fair Value estimates, a point cited as suggesting potential upside.
Summary of the largest sales
Several senior executives and directors executed large sell transactions during the reported period. Some were carried out under pre-arranged trading plans, while others followed option exercises or were effected indirectly through affiliated entities.
- Lumentum Holdings Inc. (NASDAQ: LITE) - Vincent Retort, Executive Vice President of Global Reliability & Quality, sold 38,604 shares of common stock on August 25, 2026. The sales generated approximately $32.96 million and were executed at prices that ranged from $842.2161 to $860.052 per share. The filing states the transactions were conducted pursuant to a Rule 10b5-1 trading plan Mr. Retort adopted on November 13, 2025. Following the disposals, Mr. Retort is reported to hold 78,440 shares directly. The disclosure notes Lumentum shares have since reached $956.14 and produced a 605% return over the past year. InvestingPro analysis cited in the filing assesses the stock as appearing overvalued relative to Fair Value.
- Tempus AI, Inc. (NASDAQ: TEM) - Eric P. Lefkofsky, CEO and Chairman, sold 238,052 shares of Class A common stock on August 25, 2026, for proceeds of approximately $16,286,612. The trades were executed at prices ranging from $64.03 to $70.58 per share. According to the filing, the transactions were executed pursuant to a Rule 10b5-1 trading plan Mr. Lefkofsky adopted on March 8, 2026. The shares were sold indirectly through several entities: Gray Media, LLC; Blue Media, LLC; Lefkofsky Family Foundation; and Vas.org Foundation. The filing identifies Mr. Lefkofsky as the sole manager of Gray Media, LLC and Blue Media, LLC, and as a trustee of both foundations. The disclosure notes that the stock was trading at $70.69 at the referenced time, up nearly 33% over the prior six months, and that InvestingPro analysis suggests the company appears overvalued. The filing also cites an InvestingPro Tip reporting a beta of 3.58, indicating elevated price volatility.
- CoreWeave, Inc. (NASDAQ: CRWV) - Michael N. Intrator, CEO, President, Director and a reported 10% owner, sold 307,692 shares of Class A common stock on August 25, 2026, for approximately $27.3 million. The sale prices ranged from $88.3052 to $89.9306 per share. The filings state these transactions were carried out under a pre-arranged Rule 10b5-1 trading plan Mr. Intrator adopted on November 20, 2025, and included shares held both directly and indirectly through Omnadora Capital LLC, where Mr. Intrator is identified as the sole manager of the managing entity. The filing notes CoreWeave’s share price was $86.80 at the time referenced, below the sale prices. Despite that, the company’s shares are reported up 21% year-to-date while down 16% over the past year, and InvestingPro analysis in the disclosure indicates CRWV appears undervalued based on Fair Value metrics.
- Illumina, Inc. (NASDAQ: ILMN) - Director Keith A. Meister disposed of 375,541 shares of common stock over three days between August 25 and August 27, 2026. The sales generated approximately $85.2 million and were executed at prices ranging from $224.72 to $231.23 per share. The filing breaks down the disposals: 130,019 shares sold on August 25, 106,543 on August 26 and 138,979 on August 27. The disclosure notes Illumina shares have returned 80% over the past year and were trading near a 52-week high at the time, while InvestingPro analysis cited in the filing suggests the shares remain undervalued relative to Fair Value measures.
- Mercury Systems Inc. (NASDAQ: MRCY) - William L. Ballhaus, Chairman, President and CEO, reported sales of common stock valued at over $14 million across August 25 and August 26, 2026. The sales were reported at prices ranging from $86.800 to $89.960 per share and followed the exercise of employee stock options. The filing documents option exercises to acquire 153,676 shares at an exercise price of $43.0 per share on August 25, 2026, and an additional 68,476 shares at the same exercise price on August 26, 2026. The filings report the aggregate value of the shares acquired through those option exercises as $9,552,536.
Context and takeaways
The filings include both outright open-market purchases and sales executed under pre-established Rule 10b5-1 plans, as well as transfers through trusts or related entities. Several of the sell transactions were explicitly conducted pursuant to 10b5-1 plans adopted months earlier, while other transactions followed option exercises or were reported as indirect holdings.
Investor guidance contained in the filings reiterates a commonly stated caveat: purchases and sales by insiders can reflect a range of motives. While purchases are often interpreted as a sign of confidence, sales can reflect portfolio diversification, tax planning, liquidity events or pre-scheduled plans that do not necessarily signal a change in the executive’s view of the company. The filings themselves highlight valuation commentary from InvestingPro for multiple names, signaling instances where insiders bought into names considered undervalued and where insiders sold or where InvestingPro judged the stock to be overvalued.
Key points
- Insider purchases were concentrated in energy storage, consumer staples and REITs, with directors increasing holdings in Energy Vault, Keurig Dr Pepper, Welltower and American Assets Trust.
- Large-scale divestitures were recorded in technology, biotechnology and semiconductor-related companies, including Lumentum, Tempus AI, CoreWeave and Illumina, with several sales executed under Rule 10b5-1 plans or following option exercises.
- The filings cite InvestingPro valuation notes for multiple companies, with some names appearing overvalued and others flagged as undervalued, reflecting divergent valuation assessments across sectors.
Risks and uncertainties
- Valuation risk - Several filings reference InvestingPro assessments that label certain stocks as appearing overvalued relative to Fair Value, which could affect investor expectations in the affected sectors, notably optics/semiconductors and AI-related names.
- Plan timing and intent - Dispositions executed under Rule 10b5-1 plans are often pre-scheduled and may not reflect an insider’s current view of the company, introducing uncertainty when interpreting the information as a forward-looking signal.
- Price volatility - At least one filing highlights elevated historical volatility metrics (for example a reported beta of 3.58 for Tempus), indicating that share prices for some names have been and may remain highly volatile, which is a consideration for risk management in technology and AI-related equities.
Monitoring Form 4 filings can offer one lens into how executives and directors are positioning themselves in publicly traded companies, but these disclosures are one component among many that investors should use when forming an investment view. Trades carried out under pre-arranged plans or through trusts and related entities underscore the importance of reading the details of each filing rather than inferring a single uniform message from the aggregate activity.
This article compiles information from the disclosed Form 4 filings and the valuation commentary included in those disclosures. The transactions are presented as reported in the filings without extrapolation of motive beyond what is described by the filers and the accompanying valuation notes.