This is a part of the soft gel for Vegan.
To make a soft gel pill, there are two options.
One option is to use gelatin, which is made from animal skin.
The other option is vegan. This means that it is gelatin free or free of animal products.
To make a vegan soft gel, you will need to use non-animal materials. Carrageenan is a safe, non-animal, vegan material. It is isolated from red seaweed. Although there has been some controversial about this product, its safety has been confirmed by the US Food and Drug Administration (FDA).
https://anrcatalog.ucanr.edu/pdf/8642.pdf
Between the two options, most customers choose vegan instead of gelatin.
This website explains how the vegan soft gel is made:
https://www.lusingredients.com/omega-3-to-1-vegan-soft-gels/