 grounds  (6).  You might claim that  (7)  is a non-necessitating full ground of  (6).  But one option for necessitarians is to argue that  (7)  is instead a special sort of merely partial ground, one that can’t be augmented with further facts to yield a full ground. This is how Trogdon and Witmer (2021) treat this case and, as a consequence, reject the standard definition of partial grounding (see  §1.3).  (See Chudnoff 2016; Ch. 6 and Leuenberger 2014 for discussion of other potential counterexamples to necessitarianism).