is selling stock a seasonal business?

There are a lot of people that report slow times, but to me it appears that some people or cold when others are hot. Maybe it depends on your inventory. This is still just past a year for me, so others may have more experience to speak on.

Summer holiday months are often recognised as being a slow period as well as upcoming Christmas and New Year holidays.

Summer holidays had great sales for me...

It is very strong portfolio dependent: I had the surprise to have big sales when others were complaining of low ones and vice-versa, I had low sales when others were reporting big ones. I came to the conclusion that the most important factor was my portfolio structure. For example, I have less to nothing clips related to Halloween and in the period before Halloween I get almost no sales while others get big ones.

During the winter summer footage sells, during the late summer and fall winter footage sells. People footage sells all year. Many sales are for use several months in the future.