Waterman plaque

Back in 1934 a plaque was installed at the corner of Broadway and Dey in downtown Manhattan to commemorate the 50th anniversary of Lewis E. Waterman's invention, as this clip from the March 15, 1934 Waterville Times reports:

Now Waterman's pen was hardly the first practical fountain pen, and he filed his first patent application in mid-1883, not 1884, but the Waterman company's publicists weren't going to let facts get in the way of a good story. What happened to the plaque? Like most of downtown Manhattan, Broadway and Dey has seen a lot of changes over the years.