> When I was Technical Editor, the ISSUE was copyrighted by ACM (they told
> me), but the individual article copyrights were owned by the authors. The
> implication was that any author was free to submit his or her article to
> another publication after it appeared in Ada Letters.
> I do not know whether the situation might have changed.
I don't think so. Generally ACM treats SIG newsletter articles as
"unrefereed working papers", which is technobabble for "author
keeps copyright and can publish article elsewhere".