(Whoever is doing the buying it is not showing up in this report.)
(You are correct. But, unless they reach the 5% minimum requirement for market disclosure, they wouldn't have to say/declare anything at all to the market either).
Top 20 shows holders with less than 5%, so long as they rank in the top 20.
Even a Nominee Account would appear, Nominess have delayed the paperwork revealing themselves in the past.
BND Price at posting:
79.5¢ Sentiment: Buy Disclosure: Held