In 1891, Meinhard traveled to Paris to attend a business conference at the Hôtel du Triomphe. Unbeknownst to him, his movements were being watched by agents of Professor James Moriarty, who had secretly been buying up all stakes in his company with the intention of taking it over. However, in order to complete his takeover he needed to take Meinhard out of the picture. Moriarty arranged for the Sept Grenouilles bakery, which served as the hideout of anarchist Claude Ravache, to be contracted to bake the cake for Meinhard's conference dinner. He then had Ravache plant a bomb in the cake, knowing that it would be seen as a revenge attack for the bombing in Straßburg (which Moriarty had also orchestrated). In reality, the cake was only a distraction for Sherlock Holmes, who Moriarty knew was tracking his movements. As a backup, Moriarty had his henchman Colonel Sebastian Moran, an excellent sharpshooter, stationed on the roof opposite the hotel. That way, in case Holmes managed to find the bomb in time, Meinhard would still die.
However, as things turned out, Holmes was sufficiently misled by Moriarty's red herring (that the bombing would occur at the Paris Opera during a performance of Don Giovanni) that he did not reach the hotel in time, and the bomb went off just as Meinhard was making a speech about resolving international divisions through economic cooperation. Whether he was ultimately killed by the bomb or by Moran is unknown.
Meinhard's death was beneficial in two ways to Moriarty. Firstly, it cleared the way for Moriarty to take complete control of Meinhard's weapons empire. However, it also served to further destabilize relations between France and German Empire, as it was indeed seen as a retaliation for Straßburg. The retaliatory mindset and increasing hostility between the two countries lead to the closing of the Franco-German border, making it more difficult for Holmes to follow Moriarty to the munitions plant in Heilbronn, while simultaneously bringing Europe closer to Moriarty's ultimate goal of a continent-wide war.