how did Corning invent borosilicate in 1924

[Aussie]

if Schott was already marketing it in 1893?
I'm kind of confused about the conflicting info available. Some histories state that Corning invented borosilicate in 1924. If this is true then Otto Schott couldn't have invented borosilicate and start marketing Duran by 1893. What's the real story here?

[mer]

Borosilicate glass was first developed by German glassmaker Otto Schott in the late 19th century[1] and sold under the brand name "Duran" in 1893. After Corning Glass Works introduced Pyrex in 1915, it became a synonym for borosilicate glass in the English-speaking world

http://en.wikipedia.org/wiki/Borosilicate_glass

[Spider]

I don't know why, but that makes me remember Ronald Reagan pitching borox (borax?) for Death Valley Days - damn, I'm as old as Otto