No, that isn't correct - a seller's permit is always required. That is for any business.
The law is very specific about taxes in California. It is 7.5% state sales tax, plus any additional local tax.
CA NORML also states:
If Pharmajanes is making any sales then they must have a sellers permit - so we know there is a problem because AEGY reported zero revenue - there are only two options - either Pharmajanes is selling anything or they are involved in tax evasion.