BLUEBIRD BIO INC

CUSIP: 09609G100 Class: Common Stock

RTW INVESTMENTS, LP's Holding History (CIK: 0001493215)

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

Q3 2017
Shares 104,078 Value ($000) $14,295 Avg Close — Range —
Q2 2017
Shares 104,383 Value ($000) $10,965 Avg Close — Range —
Q1 2017
Shares 103,617 Value ($000) $9,419 Avg Close — Range —
Q4 2016
Shares 122,576 Value ($000) $7,563 Avg Close — Range —
Q3 2016
Shares 87,734 Value ($000) $5,947 Avg Close — Range —
Q2 2016
Shares 612,025 Value ($000) $26,495 Avg Close — Range —
Q1 2016
Shares 226,371 Value ($000) $9,621 Avg Close — Range —
Q4 2015
Shares 5,300 Value ($000) $340 Avg Close — Range —
Q3 2015
Shares 151,594 Value ($000) $12,969 Avg Close — Range —
Q2 2015
Shares 105,000 Value ($000) $17,679 Avg Close — Range —
Q1 2015
Shares 100,000 Value ($000) $12,077 Avg Close — Range —