MERRIMACK PHARMACEUTICALS IN

CUSIP: 590328AA8 Class: NOTE 4.5% 7/1

OCONNOR, A Distinct Business Unit of UBS ASSET MANAGEMENT AM's Holding History (CIK: 0001132716)

Note: Option positions (PUT/CALL) are excluded.

Q2 2014
Shares 6,500,000 Value ($000) $8,811,000 Avg Close — Range —
Q1 2014
Shares 7,500,000 Value ($000) $7,605,000 Avg Close — Range —
Q4 2013
Shares 10,000,000 Value ($000) $10,407,000 Avg Close — Range —
Q3 2013
Shares 11,000,000 Value ($000) $10,001,000 Avg Close — Range —