PROTEOSTASIS THERAPEUTICS IN

CUSIP: 74373B109 Class: COM

Alyeska Investment Group, L.P.'s Holding History (CIK: 0001453072)

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

Q2 2018
Shares 76,277 Value ($000) $213 Avg Close — Range —
Q1 2018
Shares 79,945 Value ($000) $380 Avg Close — Range —
Q4 2017
Shares 100,000 Value ($000) $583 Avg Close — Range —
Q3 2016
Shares 75,000 Value ($000) $1,169 Avg Close — Range —