These disclosures are from 13Ds filed with the Securities and Exchange Commission. 13Ds are filed within 10 days of an entity's attaining more than 5% in any class of a company's securities. Subsequent changes in holdings or intentions must be reported in amended filings. This material is from Oct. 23 through Oct. 29, 2025. Source: VerityData
Original Filings
Astria Therapeutics(ATXS) Magnetar Financial disclosed a new position in the biopharmaceutical company of 3,312,202 shares. Magnetar purchased 3,315,218 Astria Therapeutics shares from Aug. 26 through Oct. 22 at per share prices ranging from $6.13 to $12.27 but offset some of those purchases through the sale of 1,521 shares from Aug. 26 to Sept. 11 at $6.33 to $7.84. Magnetar is probably making an arbitrage play, as on Oct. 14, Astria Therapeutics announced that it entered into a definitive agreement to be acquired by BioCryst Pharmaceuticals in a $700 million cash-and-stock deal, in which shareholders would receive an implied value of $13 per share. Following the purchases, Magnetar owns an initial 5.9% stake of Astria Therapeutics' outstanding stock.
Increases in Holdings
Viridian Therapeutics$(VRDN)$ Fairmount Funds Management raised its stake in the biopharmaceutical company to 16,025,330 shares. Fairmount Funds Management did so through the purchase of 454,545 Viridian Therapeutics shares for $22 apiece into the company's underwritten public offering on Oct. 23. Following the latest purchases, Fairmount Funds Management owns 15.1% of Viridian Therapeutics' outstanding stock. Shares of Viridian Therapeutics have gained roughly 17.3% in value in 2025.
Orthofix Medical$(OFIX)$ Juniper Investment Co. raised its stake in the medical device firm to 3,243,284 shares. Juniper Investment did so through the purchase of 398,178 Orthofix Medical shares from Sept. 26 through Oct. 17 at per share prices ranging from $14 to $15.30. Following the latest purchases, Juniper Investment owns an 8.2% stake in Orthofix Medical's outstanding stock. Shares of Orthofix Medical have lost roughly 7.2% in value in 2025.
Decreases in Holdings
Bristow Group$(VTOL)$ South Dakota Investment Council lowered its stake in the provider of vertical flight solutions to 3,056,091 shares. South Dakota Investment Council did so through the sale of 204,054 Bristow Group shares from Aug. 25 through Oct. 22 at per share prices ranging from $38.02 to $39.20. Following the latest sales, South Dakota Investment Council continues to own 10.6% of Bristow Group's outstanding stock. Shares of Bristow Group have gained about 9% in value in 2025.
Sionna Therapeutics(SION) Atlas Venture Fund XI reduced its stake in the clinical-stage biopharmaceutical company to 3,084,480 shares. Atlas Venture did so through the sale of 609,540 Sionna shares from Sept. 29 through Oct. 20 at per share prices ranging from $29.95 to $33.86. Following the latest sales, Atlas Venture continues to own 7% of Sionna' outstanding stock. Shares of Sionna have gained roughly 57.8% in value in 2025.
Email: editors@barrons.com
This content was created by Barron's, which is operated by Dow Jones & Co. Barron's is published independently from Dow Jones Newswires and The Wall Street Journal.
(END) Dow Jones Newswires
October 31, 2025 17:42 ET (21:42 GMT)
Copyright (c) 2025 Dow Jones & Company, Inc.