An illustration picture shows the Twitter logo reflected in the eye of a woman in Berlin, November 7, 2013. REUTERS/Fabrizio Bensch/Illustration/File photo

- Shares of social media company Twitter down 11.3 percent at $29.22; set for its biggest one-day percent fall in nearly five months

- Short-seller Citron Research says TWTR “has become the Harvey Weinstein of Social Media”; sets PT of $20/shr

- Amnesty International study makes Twitter “Toxic” to investors and advertisers - Citron

- Amnesty’s study with Element AI, published on Tuesday, says 7.1 pct or 1.1 mln tweets sent to 778 journalists and politicians from the United Kingdom and United States through 2017 were “problematic” or “abusive”

- “....I would note that the concept of ‘problematic’ content for the purposes of classifying content is one that warrants further discussion,” TWTR’s Legal, Policy and Trust & Safety Global Lead, Vijaya Gadde, had informed Amnesty on Dec. 12

- “It is unclear how you have defined or categorized such content, or if you are suggesting it should be removed from Twitter” - TWTR’s Gadde added

- Citron says it had been following TWTR for years but knew it had become “uninvestable” on reading the Amnesty report

- “...Twitter lags FB and Google on growth. But, any form of tweaking of the business model to ‘monitor speech’ sends traffic, engagement, and total users backwards for Twitter – a deathblow for a company playing catch up,” Citron adds

- TWTR’s stock has fallen ~7.4 percent this month, more than rival Facebook Inc’s ~5.4 percent decline, but is still up about 21.7 pct this year, compared with a 24.6 percent slide for FB during the period