Filings for Jan 12, 2022 show insider purchases at 26 companies, adding up to roughly $15.1 million. PRTA topped the list with roughly $11.2 million, led by EcoR1 Capital, LLC.
Seven of the buys came from a CEO or CFO. Cluster buying (3+ insiders) is running at 89 companies this month. One buy doesn't make a thesis, but it's a good place to start digging.