  Sum-rank metric codes have recently attracted the attention of many
researchers, due to their relevance in several applications. Mathematically,
the sum-rank metric is a natural generalization of both the Hamming metric and
the rank metric. In this paper, we provide an Anticode Bound for the sum-rank
metric, which extends the corresponding Hamming and rank-metric Anticode
bounds. We classify then optimal anticodes, i.e., codes attaining the sum-rank
metric Anticode Bound. We use these optimal anticodes to define generalized
sum-rank weights and we study their main properties. In particular, we prove
that the generalized weights of an MSRD code are determined by its parameters.
As an application, in the Appendix we explain how generalized weights measure
information leakage in multishot network coding.
