I can’t remember exactly because it’s been many moons ago 2001/2002 if i recall but largest i ever saw was when i got hung short size back in the day i think on PMCS and the FED did an emergency rate cut out of the blue.
About 10 years ago I had a fat finger. Royce Global Trust (RGT)...I thought I put it in for 1,000 share...It was for 10,000. I had the money in the account. At about 3,200 shares I noticed what I did...Thought I would get creamed!! I've made a good profit on this one...Go figure.
https://www.cnbc.com/2020/09/30/pal...-sell-shares-because-of-software-glitch-.html There is no lockup period for a direct listing, so this 3700k may just be the first of many.