Here is a detailed look at the most material insider trading disclosures filed for Tuesday for U.S.-listed companies. The activity covers both director and executive purchases as well as very large sales by major shareholders and officers. Where available, filings, transaction dates, share counts, price ranges and resulting ownership positions are reported verbatim.
Selected insider purchases
Hallador Energy Co - Director Daniel Timothy Hudson bought 10,000 shares of Hallador Energy common stock on June 29, 2026, for a reported total of $169,400. The purchases were made across multiple transactions at prices spanning $16.90 to $16.98 per share. After the acquisitions Mr. Hudson directly owns 15,000 shares of Hallador Energy common stock. The stock trades at $17.39, a modest premium to his purchase range. The filing and accompanying notes reference a market capitalization of $797.92 million and indicate the company holds more cash than debt on its balance sheet.
DLH Holdings Corp - Mink Brook Asset Management LLC, identified as a 10% owner of DLH Holdings, increased its position via several buys on June 29 and June 30, 2026. The aggregate purchases totaled 5,183 shares for $27,207, executed at prices ranging from $5.24 to $5.25 per share. The stated prices represent weighted averages across multiple transactions on each date. At the time of the filings the stock was trading near its 52-week low of $5.12, with shares down roughly 9% over the past year. The company’s market capitalization is reported as $77.68 million.
Total Return Securities Fund - Director Moritz A. Sell increased his holdings through open-market purchases totaling $24,155, according to a Form 4 filed with the Securities and Exchange Commission. Mr. Sell acquired 2,091 shares on June 26, 2026 and an additional 2,000 shares on June 29, 2026. The prices paid were reported in a range from $5.885 to $5.925 per share.
Capital Southwest Corp - Director Ramona Lynn Rogers-Windsor purchased 210.9615 shares of Capital Southwest common stock on June 30, 2026 at $23.701 per share, a transaction totaling approximately $4,999. The filing notes the share price was trading near its 52-week high of $24.43, with the then-current price at $23.77. The filing also references a dividend yield of 14.18% as reported by InvestingPro. Following the purchase Ms. Rogers-Windsor directly holds 23,090.6758 shares of Capital Southwest common stock.
Central Securities Corp - CEO and President John C. Hill reported purchases totaling $12,085 on June 26, 2026. Mr. Hill purchased 233 shares of Central Securities common stock at $51.87 per share. Of these, 228 shares were acquired directly, increasing his direct holdings to 77,601 shares. An additional five shares were acquired indirectly through his children, bringing the total indirect ownership in that category to 906 shares. Central Securities shares trade at $52.51, and the filing notes a price-to-earnings ratio of 5.85. The company has maintained dividend payments for 54 consecutive years, with a reported yield of 1.19%.
Selected insider sales
Perimeter Solutions, Inc - WindAcre Partnership LLC, identified as a 10% owner, sold a substantial block of ordinary shares between June 26 and June 30, 2026. The partnership disposed of 5,706,579 ordinary shares for aggregate proceeds of approximately $195.6 million. Sales prices ranged from $33.00 to $36.25 per share. After these transactions WindAcre Partnership LLC directly owns 16,148,621 ordinary shares of Perimeter Solutions. The stock trades at $35.65, near its 52-week high of $38.17, and has posted a 156% gain over the past year. The filing notes InvestingPro analysis lists the company among the Most Overvalued names at current prices.
Micron Technology Inc - President and CEO Sanjay Mehrotra sold common stock totaling $32,761,315 on June 26, 2026. The sales involved 26,736 shares at prices between $1,128.41 and $1,169.96 per share. The transactions were carried out pursuant to a Rule 10b5-1 trading plan that Mr. Mehrotra adopted on January 30, 2026. At the time of the filing Micron shares were trading at $1,153, near their 52-week high of $1,255, after an extraordinary 839% gain over the prior year.
Kymera Therapeutics, Inc - Director Bruce Booth reported sales of 500,000 shares of Kymera Therapeutics common stock for total proceeds of $56,460,136. The transactions occurred on June 26 and June 29, 2026, at prices ranging from $105.78 to $118.66 per share. These sales were completed pursuant to a Rule 10b5-1 trading plan adopted on December 11, 2025. The shares were held indirectly by Atlas Venture Fund X, L.P. and Atlas Venture Opportunity Fund I, L.P. The filing notes Mr. Booth is a member of the general partners of those funds and disclaims beneficial ownership of the securities held by them, except to the extent of his pecuniary interest. Kymera shares trade at $114.69 and have risen approximately 150% over the past year; InvestingPro commentary cited in the filing indicates the stock appears overvalued relative to its Fair Value.
Guardant Health, Inc - Co-Chief Executive Officer and director AmirAli Talasaz sold common stock totaling roughly $39.3 million and concurrently acquired shares through option exercises valued at about $1.1 million between June 26 and June 29, 2026. The sales amounted to 260,000 shares at prices from $150.4886 to $153.0 per share, trading near the stock’s 52-week high of $153.95. The filing highlights a 195% return over the past year for Guardant Health and notes InvestingPro’s Fair Value analysis suggests the stock is currently overvalued. All sold shares were held indirectly by the Talasaz and Eskandari 2017 Family Trust.
Oscar Health, Inc - Director Mario Schlosser sold Class A common stock totaling about $30.18 million on June 23, 2026. The sales were executed under a Rule 10b5-1 trading plan and involved 1,027,490 shares, with prices ranging from $28.08 to $30.09 per share. The stock trades at $28.46, near its 52-week high of $30.66, following a 105% increase over the past six months. The filing details that the transactions included both direct holdings and shares held indirectly through family trusts. The disclosure also cites InvestingPro analysis that describes recent strong returns and elevated volatility, noting a beta of 2.39 and that the stock appears to be trading near fair value.
Context and takeaways
The fresh batch of Form 4 filings and related disclosures highlights a split between smaller-scale insider purchases and large-scale selling by corporate insiders and major shareholders. The purchases reported here are modest in dollar terms and concentrated at smaller capitalization firms where directors boosted direct holdings or where 10% owners increased stakes through measured buys. By contrast, the selling activity includes very large, multi-million-dollar dispositions by a 10% owner at Perimeter Solutions and by senior executives at larger, higher-profile companies.
Several of the sales were executed under Rule 10b5-1 trading plans, a commonly used mechanism that permits pre-specified transactions and is explicitly referenced in a number of the filings. The filings also note instances where sales were indirect or effected through family trusts or investment vehicles, as in the cases of Kymera, Guardant Health and Oscar Health.
Insider buying and selling can offer investors one piece of the puzzle when assessing management sentiment and major-holder positioning. Purchases may signal confidence or an intention to increase or maintain exposure, while sales can reflect diversification, liquidity needs, or use of prearranged plans. These transactions should be weighed alongside company fundamentals, valuations and other market signals, including the valuation commentary referenced in the filings for a number of these names.
Methodology note
The trades summarized here are drawn from Form 4 filings and other SEC disclosures referenced in the filings. Reported share counts, price ranges, dates and ownership positions are presented as disclosed in those filings and in the accompanying company data cited within those filings.