Who owns CALL (SH) PROSHARES SHORT NOV 20 15 $21 (100 SHS)? Institutional holders

CALL (SH) PROSHARES SHORT NOV 20 15 $21 (100 SHS): summary

No institution's latest stored 13F report lists CALL (SH) PROSHARES SHORT NOV 20 15 $21 (100 SHS).