The slump extended losses on Thursday after Hindenburg Research accused the electric-vehicle company and its CEO, Trevor Milton, of overhyping its truck's capabilities. The firm, which has a short position in Nikola, also accused Nikola of filling its multibillion-dollar order book "with fluff."
Citron Research backed up the claims on Friday morning and congratulated Hindenburg in a tweet, saying it was "exposing what appears to be a total fraud" with Nikola.
Citron pledged to cover half of any legal expenses for Hindenburg.
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