“This is the most painful decision of my professional career,” said DeYoung, who helped found the band 35 years ago in Chicago.

DeYoung said a partnership contract renewed in 1990 by him, Tommy Shaw, James Young, Chuck Panozzo and Panozzo’s brother, John, required all five to agree on matters concerning the band and the Styx trademark. John Panozzo died in 1996.

“Now they have taken the band’s name and excluded me from the decision-making process,” said DeYoung, who filed a federal lawsuit in Chicago October 10 claiming misuse of the Styx trademark.

DeYoung joined the 1997 Styx reunion tour but asked the others to delay their 1999 tour because he was suffering side effects of Epstein-Barr Syndrome.

Last month, the singer told Pollstar he had been ill since early 1998 and was finally diagnosed with the mysterious, energy-sapping illness in the spring of ‘99.

Shaw and Young, the only long-time members on the current Styx tour, are performing in Canada this week and had no comment. “No one within the Styx organization knows anything about a lawsuit filed by Dennis DeYoung,” manager Charlie Brusco said.

In June, Young told the Chicago Sun-Times that the decision to tour was a case of “majority rules.” DeYoung is “going off in a very unilateral sort of way, where it’s his way or the highway. We chose the highway,” Young said.

Even though he still suffers from light sensitivity, DeYoung said he has recovered his strength and is ready to perform. Next month, he returns to the stage for four theatre dates, backed by a local 50-piece orchestra.

In his interview with Pollstar, he refrained from saying anything negative about his Styx bandmates and he certainly hasn’t lost his affection for the music. His theatre show includes a number of Styx classics

Now that he’s feeling better, DeYoung said he’d like to perform more often.