The Pioneer Glass Company was in business for a short period of time in 1984 in the old Imperial factory in Bellaire, Ohio. Their pieces all have the SIC mark (Save Imperial Committee) and some of them have an I inside a G.
The labels on the Pioneer pieces are all original from Pioneer. Many of their molds were from Imperial, but they also had some from Fostoria and from Fred Wilkerson (who was one of the glassmakers involved in this attempt to keep Imperial going). In addition to the marks mentioned above, some pieces are also marked with a PG mark.