Quantum-Si (NASDAQ: QSI) stock saw some big pricing swings in Friday's trading. While the protein-sequencing technology specialist's share price closed out the day down 6.2%, it had previously been up as much as 12.8% in the daily session, according to data from S&P Global Market Intelligence.

Quantum-Si started Friday with a bang following news that Ark Invest had purchased 1.4 million shares of the company's stock the day prior. Ark Invest is led by CEO Cathie Wood, and news that the high-profile growth investor has purchased a stock for her company's exchange-traded funds (ETFs) can sometimes create additional bullish momentum for that company's share price. 

Ark Invest publicly discloses its stock positions on its websites, and regular updates for the portfolio compositions of its funds show what stocks Wood's company has bought and sold. With an update published Thursday, the investment firm revealed that it purchased roughly $3.7 million worth of Quantum-Si shares for its ARK Genomic Revolution ETF (NYSEMKT: ARKG). It wasn't a new position for the ETF.

Continue reading

Source Fool.com