observed anecdotal experience evidence but the stocks he targets generally do see a sharp positive impact shortly after crashing. Definitely more than the average.
That’s from the low point. But the stocks themselves don’t always fully recover, sometimes they do. But there are almost always short term gains.

A few years ago he targeted Tesla. Look where they are.

Here are some of the most recent ones:

A few months ago he targeted IDEX. It went from around 4 to hang out around 1.2-1.3 for a while. I got in at an average of 1.23. Within a few weeks it went to 1.7 or so. I got out at 1.45 I think. It has since shot down to low 1s today. The allegations against IDEX were thoroughly refuted and some pretty shady tactics by Hindenburg were exposed. Yet, the stock is currently way lower than when the hit job happened. But the short term gain was definitely there.

WKHS was another recently targeted. They are now trading at all time highs.at 23.7 over about 15 when the report came out. Allegations were totally false or misleading.

PRK was targeted about a month ago. Is now trading about 10% higher than when the hit job happened.

SRNE is one of the only recent ones that has consistently tanked with no bounce. IMO this one was more of a correction to undeserved short term hype - the type of thing you see in bio stocks all the time - rather than something Hindenburg did. He was more the catalyst, but did nothing groundbreaking.

In my anecdotal observations over the last couple years it seems to be about 70-80% of the stocks that he targets sees a short term bounce at minimum.