From their spec sheet (https://www.vomboden.com/wp-content/uploads/2018/12/vomboden-GS-Brand-1907-FINAL.pdf, retrieved March 2021)
"No sulfur or filtration on “Pur” wines. For 1Ls, no fining and no filtration in most vintages. If filtration is needed, then it is very light and no animal products are used, so all wines are vegan."
Brand Riesling Pur
by Brand Bros
Vegan
This product is listed as vegan friendly.
What the company told us
Correspondence on record, with the date of each entry.