Last dividend's (other than the 4 gnbt to 1 ngio) ex date was Nov. 30, 2018, when generex gave back to the shareholders a 21 to 1 stock dividend.....below are the prices and pr's that were circulating at the time.......

Closing Open High Low Volume

Nov. 30, 2018 18.90 17.85 19.32 16.17 338,541

Dec. 3, 2018 1.99 1.04 3.00 1.04 1.14 m
Dec. 4, 2018 1.70 1.85 2.45 1.65 727,902
Dec. 5, 2018 no data
Dec. 6, 2018 1.10 1.63 1.63 .91 1.19 m
Dec. 7, 2018 1.00 1.07 1.21 .95 443,702

Nov. 26: https://www.businesswire.com/news/home/201811...h-Alkaline
Nov. 27: https://www.businesswire.com/news/home/201811...ment-NSABP
Nov. 28: https://www.prnewswire.com/news-releases/gene...56126.html
Nov. 28: https://www.bloomberg.com/press-releases/2018...ement-team
Nov. 29: https://markets.businessinsider.com/news/stoc...1027767080
Nov. 30: https://www.businesswire.com/news/home/201811...Management
Dec. 3 : https://www.biospace.com/article/releases/gen...rant-deal/
Dec. 4: https://www.businesswire.com/news/home/201812...Conference

as you can see they were busy bees b4 the 20:1 dividend.....