40 companies had the people running the company buying at market prices in filings dated Aug 9, 2021, about $46.1 million combined. The biggest was CDLX (Cardlytics, Inc.), where SOSIN CLIFFORD led about $32.3 million of buying.
Cluster buying (3+ insiders) is running at 70 companies this month. C-suite buying: 11 companies. One buy doesn't make a thesis, but it's a good place to start digging.