While 33 Verizon IndyCar Series racecars circulated Monday around the 2.5-mile Indianapolis Motor Speedway in preparation for this Sunday’s 100th Indianapolis 500, the series’ attorneys were busy presenting a breach-of-contract lawsuit against The Boston Grand Prix LLC and its organizers John Casey and Mark Perrone.

The Boston street race scheduled for the Labor Day weekend and intended for September 4, was announced in May of last year. The event has been fraught with difficulties nearly since its presentation to the IndyCar community.

The track’s organizers met with dissension from the general public from the get-go and, despite claims of very good ticket sales and corporate partnerships, the organizers had to cancel the event at the end of April, claiming they were being hit with increasing demands from the city that were both financial and physical in nature. Every time they turned, the group said, another demand created yet another roadblock for them.

According to Indianapolis Business Journal (IBJ) Daily, a website that monitors goings-on in the city, the suit was filed in Indianapolis Federal court on Monday. Details of the suit are not available as it was filed under seal; the IBJ report stated that INDYCAR would not release further information because the filings contain “trade secret and commercially sensitive business and financial information.” These bits of information include the agreement which intended for the event to remain on the schedule through the Labor Day weekend of 2020.

In the complaint INDYCAR noted, “The public interest will be served by prohibiting access to this sensitive and proprietary information, and INDYCAR would face a significant risk of substantial harm if the information were disclosed.” The type and manner of recompense being sought by INDYCAR is not clear at this time.

The sanctioning body also filed a redacted complaint, the IBJ report stated, which will become public 14 days from its filing. That complaint won’t include the pertinent information on INDYCAR pricing structures, its sanction fees and other financial agreements it keeps close to the vest.

Within 14 days of announcing the cancellation of the Boston Grand Prix, INDYCAR replaced the Labor Day weekend event with a road race at Watkins Glen International in New York, formerly an historic and traditional stop for Indy cars throughout the decades.