Yes, during the rounds where VCs are stepping over themselves to invest, founders can negotiate terms that permit them (and their employees and early investors)

Yes, during the rounds where VCs are stepping over themselves to invest, founders can negotiate terms that permit them (and their employees and early investors) to sell some of their stock as part of the deal, in a secondary sale (https://rizstanford.medium.com/secondary-sales-in-vc-backed-startups-a-quick-primer-for-entrepreneurs-bdc25ea7f39a https://rizstanford.medium.com/secondary-sales-in-vc-backed-...).