WESTFIELD CAPITAL MANAGEMENT CO LP - MAST THERAPEUTICS INC ownership

MAST THERAPEUTICS INC's ticker is MSTX and the CUSIP is 576314108. A total of 35 filers reported holding MAST THERAPEUTICS INC in Q2 2013. The put-call ratio across all filers is - and the average weighting 0.1%.

Quarter-by-quarter ownership
WESTFIELD CAPITAL MANAGEMENT CO LP ownership history of MAST THERAPEUTICS INC
ValueSharesWeighting
Q3 2013$148,000
+2.1%
337,6000.0%0.00%0.0%
Q2 2013$145,000337,6000.00%
Other shareholders
MAST THERAPEUTICS INC shareholders Q2 2013
NameSharesValueWeighting ↓
JAY JEFFREY R 5,800,000$2,490,0001.97%
SABBY MANAGEMENT, LLC 7,711,867$3,310,0000.22%
Ancora Advisors LLC 1,848,045$793,0000.14%
DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) 3,948,302$1,695,0000.08%
Alyeska Investment Group, L.P. 1,900,000$1,631,0000.08%
Alyeska Investment Group, L.P. 3,800,000$1,631,0000.08%
SHEPHERD KAPLAN KROCHUK, LLC 894,401$384,0000.08%
PERKINS CAPITAL MANAGEMENT INC 140,000$60,0000.05%
Pine River Capital Management L.P. 2,578,486$1,106,0000.02%
OCONNOR, A Distinct Business Unit of UBS ASSET MANAGEMENT AMERICAS (LLC) 794,900$341,000,0000.01%
View complete list of MAST THERAPEUTICS INC shareholders