Billy Corgan has said that he might split up Smashing Pumpkins following the release of two planned albums in 2015.
Mr. Corgan can do whatever he wants, but to pretend that Smashing Pumpkins are a band at this point is ridiculous. This is what he has decided to call his solo work because that band, as constituted in the early 1990s, hasn't existed in a long, long time.
It's a brand name. It's not the name of anything that resembles the original band.