The quote I included made it pretty clear that #ad was conditionally acceptable if it prefixes the message. It also made it clear that #sp and #spon are never s

The quote I included made it pretty clear that #ad was conditionally acceptable if it prefixes the message. It also made it clear that #sp and #spon are never sufficient. I saw no further notes on #sponsored, but my common sense would group it with #ad if I had to choose between the two options presented.