QuantumSi is trading at $1.41, down 8.17% at 9:38 a.m. EST on October 12, 2026; no clear company-specific announcement or event explaining the decline was found.
- QuantumSi’s October 8 update reported detection of 19 amino acids in its Proteus development program, but available coverage does not connect that news to the drop.
- The supplied market context shows only modest index moves and does not establish a broader-market explanation.