Equine sarcoids are the most common skin tumors in horses and other equids. In their pathogenesis, thebovine papillomavirus (BPV) plays a major role. Many clinical manifestations have been described, rangingfrom small single lesions to multiple aggressively growing masses. Histopathologically, it is consideredas a biphasic tumor with epidermal hyperplasia and subepidermal proliferation of transformed fibroblasts.The diagnosis can be made clinically, histopathologically and/or by detection of BPV DNA. Sarcoidscan appear on any part of the body, but they are mostly localized on the ventral abdomen, the paragenitalregion, head and limbs. Sarcoids occur independent of breed, coat color, sex or age, but they develop morecommonly in young adults and certain families and breeds are more vulnerable than others. Transmissionof BPV is supposed to happen from cattle to horse or from horse to horse, possibly via insects.