Insider Trading Weekly: The Biggest Buys And Sells

Boston Scientific makes cardiovascular, electrophysiology and medical-surgical devices, and the purchase is the largest genuine open-market buy of the week by some distance. On 29 July the company reported second-quarter net sales of $5.442 billion, up 7.5 per cent as reported and 7.0 per cent organically, with adjusted earnings of $0.86 per share against a prior guidance range of $0.82 to $0.84. It also set full-year 2026 guidance at revenue growth of about 5.5 to 6.5 per cent reported and adjusted earnings of $3.28 to $3.32, the second consecutive quarter in which the outlook was trimmed, with electrophysiology and Watchman named as the soft spots. The year has also brought two device actions: a Class I correction covering 718,456 pacemakers and cardiac resynchronisation devices in the Accolade, Proponent, Essentio and Altrua 2 families, published by the FDA on 24 April 2026 as recall Z-1770-2026, and a Class II recall of Faradrive steerable sheaths used with the Farapulse pulsed-field ablation system over an air-embolism risk, published on 20 July 2026 as recall Z-2756-2026 and covering 508,151 units in the United States and about 193,000 elsewhere. Michael Mahoney bought 186,240 shares at a weighted average of $48.33 on 3 August, five days after the guidance cut, and the Form 4 carries no 10b5-1 plan. The same filing separately records 22,119 shares acquired through a discretionary rebalancing inside the company 401(k).

Braveheart Bio is a cardiovascular company working on hypertrophic cardiomyopathy, in both its obstructive and non-obstructive forms. Its lead candidate, BHB-1893, is an oral cardiac myosin inhibitor licensed from Hengrui; earlier-phase work has been completed largely in China and a Phase 3 programme is planned rather than under way. The company priced an upsized offering of 21,250,000 shares at $18.00 on 5 August for $382.5 million gross, trading opened on Nasdaq on 6 August, and on 7 August it announced the closing with the underwriters’ option exercised in full, taking the total to 24,437,500 shares and $439.9 million. The four purchases in the table, by Forbion, chief executive Travis Murdoch, director Christopher Viehbacher and director David Lubner, are all at a flat $18.00 and all dated 7 August. They are allocations taken in the deal at the offer price, not shares bought from other investors in the market, which is why they sit at the top of a buy ranking without telling you anything about what anyone thought of the price once it was trading.

Attovia Therapeutics is an immunology company built around ATTOBODY, a biparatopic biologic platform. Its clinical-stage asset is ATTO-1310, an anti-IL-31 antibody aimed at chronic pruritic conditions; ATTO-2306 and ATTO-1091 remain in IND-enabling work rather than in the clinic. The company priced an upsized offering of 17,000,000 shares at $17.00 on 4 August for $289.0 million gross, with an option over a further 2,550,000 shares. Redmile Group, Frazier Life Sciences XI and Sanofi each filed a Form 4 as a holder of more than ten per cent reporting a purchase at exactly $17.00 on 6 August. Sanofi’s filing is the one that also records the conversion of its Series C preferred stock into 782,855 common shares, which is the mechanical result of the listing rather than a decision taken that week.

Apnimed develops oral pharmacological treatments for sleep-disordered breathing. Its lead candidate AD109 combines aroxybutynin and atomoxetine in a once-daily pill for obstructive sleep apnoea, an indication where the standard of care is a device rather than a drug. The company reported positive topline results from SynAIRgy, a Phase 3 trial that met its primary endpoint on the change in apnoea-hypopnoea index at 26 weeks with a p-value of 0.001. It priced an upsized offering of 12,000,000 shares at $16.00 on 30 July for $192 million gross, began trading on 31 July, and announced the closing on 3 August with the underwriters’ option exercised in full for a total of 13,800,000 shares and $220.8 million. Morningside Venture Investments, already a holder of more than ten per cent, reported 312,500 shares at the $16.00 offer price on 3 August.

Aptiv supplies vehicle electrical architecture, connectors and advanced safety electronics to the global car industry. Director Paul Meister bought 105,631 shares for $4,999,959 on 5 August, a round dollar amount put to work at whatever the shares cost that day, with no 10b5-1 plan on the filing. It is the second-largest open-market purchase of the week and the largest by a non-executive director. Aptiv reported second-quarter results on 4 August 2026; the figures in that release are not restated here because they were not confirmed against the company’s own announcement in time for publication.

CoStar Group runs commercial-property data and marketplace businesses including CoStar, LoopNet, Apartments.com, Homes.com and Matterport. Founder and chief executive Andrew Florance bought 83,300 shares at a weighted average of $29.89 on 4 August, about $2.49 million, with no 10b5-1 plan on the filing. Founder purchases carry a different weight from those of hired executives, because the holding is usually already large enough that adding to it changes little except the signal.

Two Pfizer directors bought on 5 August without a plan on either filing: Ronald Blaylock took 39,231 shares at a weighted average of $25.46 for about $999,000, and Mortimer Buckley, formerly chief executive of Vanguard, took 37,632 shares at $25.52 for about $960,000. Neither is large in the context of a company of Pfizer’s size, and neither is decisive on its own. Two directors chose the same session, and board members are the insiders least likely to be trading on a schedule.

Churchill Capital Corp XIII is a blank-cheque company with no operating business. Michael Klein’s $3.5 million on 3 August is 350,000 private placement units subscribed at the $10.00 trust price, the standard mechanism by which a sponsor funds the trust account and the costs of looking for a target. It appears in insider rankings as a large purchase because the filing is a Form 4 like any other. It is a cost of setting up the vehicle, and it is why a shell company sits above every operating business in the table except Boston Scientific and the three new listings.

Kenta Kon, president of Toyota Motor, bought 85,000 ordinary shares on 5 August. The Form 4 footnote records that the purchase was settled in yen and converted into dollars for the filing, which is why the reported price of $18.41 bears no relation to the depositary share that trades in New York at roughly ten times that. The dollar total of about $1.56 million is correct. Purchases by senior Japanese executives are reported to the SEC because Toyota has a US listing, and they appear rarely in these filings.

Four smaller purchases complete the open-market side. Peter Huntsman, chairman and chief executive of the chemicals producer that carries his name, bought 100,000 shares at $9.81 on 3 August for $981,000, in a stock that trades in single digits after a long downturn in commodity chemicals. Ingersoll Rand director Aurobind Satpathy bought 11,538 shares at $86.68 on 3 August for about $1.0 million. SiteOne Landscape Supply chief executive Doug Black bought 8,000 shares at $102.03 on 4 August for $816,280. American Bitcoin director Justin Mateen bought on two consecutive sessions, 144,543 shares at a weighted average of $6.40 on 5 August and 162,438 shares at $6.19 on 6 August, about $1.93 million in all, adding on the way down rather than into strength.