Octopus Investments and Vanguard Group disclose sizable stakes in UK firms Advanced Medical Solutions and Senior plc

Octopus Investments Ltd filed a Form 8.3 opening‑position disclosure showing it holds 19,934,831 ordinary 5p shares of Advanced Medical Solutions Group plc, representing roughly 9.0% of the company, with a recent sale of 29,607 shares. The disclosure, dated 25 June 2026, complies with Rule 8.3 of the UK Takeover Code.

The Vanguard Group, Inc. submitted a separate Form 8.3 showing ownership of 21,689,886 ordinary 10p shares in Senior plc, amounting to about 5.2% of that firm’s equity, and a sale of 6,165 shares on the same date. Both filings detail the investors’ positions, short holdings and any derivative arrangements, and are publicly recorded under the Takeover Code requirements.