Masimo (NASDAQ: MASI) shares soared 8.7% in the last trading session to close at $121.42. The move was backed by solid volume with far more shares changing hands than in a normal session. This compares to the stock’s 8.5% loss over the past four weeks. The sharp upsurge in Masimo’s shares can be attributed to the surprising news regarding the company’s newly elected Board of Directors. On Sept. 19, per a public statement issued from Politan, activist investor Quentin Koffey, and his Politan Capital Management group’s proposed candidates, both won election to the two available Board seats of Ma…