"Overall, as management tiptoes into the background after cashing out, we believe Equinix's hefty valuation premium, claimed market leadership and growth prospects will soon reverse course, " Hindenburg said. Hindenburg also revealed it had taken a short position against Equinix, which has a market cap of near-US$80 billion, on the back of the research. "We are investigating the claims and we will respond in due course," an Equinix spokesperson said on Wednesday, meanwhile. Equinix shares fell 4.8% to US$804.23 on the news.