Retirees are being promised that they will be able to con­tin­ue their health cov­er­age for the rest of their lives, or until they turn 65 and qual­i­fy for Medicare…or until the employ­er changes their mind.  In the case M&G Poly­mers USA LLC vs. Tack­ett the col­lec­tive bar­gain­ing agree­ment allow­ing for life­time cov­er­age has been chal­lenged.  Rules about what must be said or what must be inferred when the agree­ment is oth­er­wise silent are all under con­sid­er­a­tion here.