UBS sell after speculation of store closes, then buy 9 mill shares back, page-4

They are emulating Nathan Meyer Rothschild

https://www.investopedia.com/updates/history-rothschild-family/

"On July 18, 1815, a courier working for Rothschild informed the English government that Napoleon appeared to be suffering defeat at Waterloo. The English government, believing instead that they were losing the battle, dismissed the courier's report and believed it to be false information. At this point, with England's future seeming dire, Rothschild began selling all of his bonds, encouraging rumors that Napoleon had won and that English government paper would soon be worthless. Due to Rothschild's reputation as an influential, renowned and respected investor, the panicked English public followed his lead. The mass selling resulted in a total collapse of the English stock exchange. It was then that Rothschild's agents began snatching up bonds and stock at record-low prices".