American Caresource Holdings, Inc. | 2013 | FY | 3

A summary of stock warrant activity is as follows:
 
Outstanding Warrants
(thousands)
Weighted-Average Exercise Price
Outstanding at December 31, 2011
158

$
5.25

Granted
—

—

Cancelled
(114
)
$
4.15

Outstanding at December 31, 2012
44

$
1.50

Granted
—

—

Cancelled or expired
—

—

Outstanding at December 31, 2013
44

$
1.50

Vested at December 31, 2013
22

$
1.50

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