This is a post mostly to myself, so that when I forget this I can come here and check it out :)
(I forget about ctrl-b from time to time)

When copying diagrams from Enterprise Architect you can use ctrl-B to include the swim-lanes. A normal ctrl-c will not give you the swim-lanes. A side effect is that ctrl—b gives you a copy of the whole diagram, you cannot select what objects to copy. So marking objects first or pressing ctrl-A to selects all is both unnecessary and meaningless since ctrl-b seems to mean: “copy the whole diagram now and include all the stuff in there, even the swimlanes” (which ctrl-A, ctrl-C does not).