To answer your question though, probably most individual stock purchases by lawmakers do not constitute insider trading.

A lot of rich people get early access to IPOs and zillions of other favorable investments. That could well have more to do with the average net worth of lawmakers, especially senators, than insider access.

The FEC looks at individual trades when collecting evidence of insider trading - it only takes one trade to convict. I still don't see what the stocks you mentioned have to do with anything. Most of them IPOed before Pelosi was elected.