GRAN TIERRA ENERGY INC

CUSIP: 38500T101 Class: COM

Horizon Investment Services, LLC's Holding History (CIK: 0001426940)

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

Q1 2014
Shares 29,950 Value ($000) $214 Avg Close — Range —
Q4 2013
Shares 33,835 Value ($000) $247 Avg Close — Range —
Q3 2013
Shares 31,040 Value ($000) $220 Avg Close — Range —