The petition was filed Tuesday. Overnite has contacted the NLRB to schedule a decertification election.
The Teamsters union has been trying to unionize Overnite for five years, and has been staging an unfair labor practices strike against the less-than-truckload company since last October.
According to the Teamsters, the union represents about 3,700 of Overnite's 8,200 drivers and dock workers. However, Overnite says the union represents less than 1,800 of Overnite's 13,000 employees.
In Toledo, where the teamsters represent 45 freight handlers, five full-time and two part-time
employees are honoring the picket lines, according to Overnite.