Secondary offerings

Hi Pat, I got a question on the matter of secondary offerings in regarrd of Dynatrace breakout on 6th of january. Also secondary offerings in general.. Is the shares in the so called secondary offering new share issues or are shares already in the market and therefore shares switches hand on the date the filing is published? Is it just large shareholder want to reduce their risk? Thank you, best regards Robert from Norway. (No, there are no polar bears in the streets.. yet.. futures are gaining some over night loss):))