Russia, in support of Serbia, declared partial mobilization against Austria-Hungary. German Chancellor Bethmann-Hollweg waited until the 31st for an appropriate response, when Germany declared Erklärung des Kriegszustandes or State of Danger of War.
The exchange was closed shortly after the beginning of World War I (July 31, 1914), but it partially re-opened on November 28 of that year in order to help the war effort by trading bonds and completely reopened for stock trading in mid-December.