> Do you know what the rules are around defining a bargaining unit? Is this completely up to the union? Or are there rules?
The union can basically claim whatever unit they want, within reason (and then some). It's completely legal to define membership as a requirement for inclusion in the bargaining unit. Beyond that, the boundaries are usually drawn by things like job title, role/responsibility, geographical location, etc.).
Unions can also retroactively redefine bargaining units after elections and use that as an argument to invalidate elections that they lose. In theory the NLRB is responsible for judging this, but they tend to favor the unions heavily, which is one of the reasons that decertifying a union is nearly impossible in practice - even if the employees win the election to decertify their union, the union could claim that the bargaining unit is different, and that they didn't get a majority of the new unit.
The union can basically claim whatever unit they want, within reason (and then some). It's completely legal to define membership as a requirement for inclusion in the bargaining unit. Beyond that, the boundaries are usually drawn by things like job title, role/responsibility, geographical location, etc.).
Unions can also retroactively redefine bargaining units after elections and use that as an argument to invalidate elections that they lose. In theory the NLRB is responsible for judging this, but they tend to favor the unions heavily, which is one of the reasons that decertifying a union is nearly impossible in practice - even if the employees win the election to decertify their union, the union could claim that the bargaining unit is different, and that they didn't get a majority of the new unit.