Janus Henderson Group plc Acquires 14.4% Stake in ProMIS Neurosciences Inc.

On April 7, 2026, Janus Henderson Group plc filed a Schedule 13G disclosing a new significant stake in ProMIS Neurosciences Inc. (PMN). As of the event date on March 31, 2026, the investment firm reported beneficial ownership of 1,292,757 common shares, representing a 14.4% ownership stake in the company. This position was established from a previous holding of zero shares, marking a substantial new entry for the filer. Janus Henderson Group plc serves as the ultimate parent company for several SEC-registered investment advisers, including Janus Henderson Investors US LLC and Janus Henderson Investors UK Limited. The filing indicates that the shares are held across various managed portfolios, with the Janus Henderson Biotech Innovation Master Fund Ltd. specifically identified as having the right to receive dividends or sale proceeds from more than five percent of the issuer's common shares. The securities were acquired in the ordinary course of business and not for the purpose of influencing or changing the control of the issuer.