I am thinking that this should be an opt-in rather than opt-out for
GDPR compliance. However it is difficult to accomplish in my
opinion... So opt-out can be really a compromise here.
We can tell the attendees we are giving such info to these agencies.
I will ask MEET TAIWAN next week if having initials and nationality
per person is sufficient for their requirements.
"Y. W.", "Taiwan"
"C. C.", "Taiwan"
Also along with the (partial) list of attendees, we can give
statistics of nationality to them to further telling them we have such
many people. (Though, I asked MEET TAIWAN and they don't accept us
giving statistics *instead of* list of attendees.)
Sending the email again because mailing list considering my email spam.