yes, Blackrock has such list and somewhere in the past (2, 3?) years it has been posted here on the PPHM board. But I don't know by who and when. PPHM was in that list.
If you go on Nasdaq site and click on Institutional Holdings for PPHM you will see all the institutions with ownership. Click on the institution you want to look up and it will list all the positions they hold. One Blackrock fund has 3,901 positions so if pphm tanks they are well diversified.
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