When someone says heretofore, they're describing things that have happened up to the present moment. This formal word means "thus far" and often appears in legal or other official documents.
This is an old-fashioned word, but it refers to something timeless — events in the past that have gone on until now. To sell a new shoe, an advertiser could say, "Heretofore, there has never been a shoe like this." After a disaster, someone could say, "Heretofore, we never experienced such a catastrophe." This word draws a line in the sand between the past and the present. This word means about the same as as yet and until now.