  A dominating set S of graph G is called metric-locating-dominating if it is
also locating, that is, if every vertex v is uniquely determined by its vector
of distances to the vertices in S. If moreover, every vertex v not in S is also
uniquely determined by the set of neighbors of v belonging to S, then it is
said to be locating-dominating. Locating, metric-locating-dominating and
locating-dominating sets of minimum cardinality are called b-codes, e-codes and
l-codes, respectively. A Nordhaus-Gaddum bound is a tight lower or upper bound
on the sum or product of a parameter of a graph G and its complement G. In this
paper, we present some Nordhaus-Gaddum bounds for the location number b, the
metric-location-number e and the location-domination number l. Moreover, in
each case, the graph family attaining the corresponding bound is characterized.
