SIGMA ALDRICH CORP | 2013 | FY | 3


Intangible Assets
The Company's amortizable and unamortizable intangible assets at December 31, 2013 and 2012 are as follows:
 
 
Cost
 
Accumulated Amortization
 
2013
 
2012
 
2013
 
2012
Amortizable intangible assets:
 
 
 
 
 
 
 
Patents
$
14

 
$
14

 
$
9

 
$
8

Licenses
48

 
47

 
22

 
17

Customer relationships
254

 
255

 
77

 
61

Technical knowledge
48

 
48

 
19

 
15

Other
29

 
29

 
23

 
22

Total amortizable intangible assets
$
393

 
$
393

 
$
150

 
$
123

Unamortizable intangible assets:
 
 
 
 
 
 
 
Goodwill
$
717

 
$
717

 
$
26

 
$
26

Trademarks and trade names
20

 
20

 
8

 
8

Total unamortizable intangible assets
$
737

 
$
737

 
$
34

 
$
34


During the year ended December 31, 2013, the Company did not acquire any intangible assets or goodwill. During the year ended December 31, 2012, the Company added $155 of acquired intangible assets and $222 of acquired goodwill for acquisitions made during 2012.
The Company recorded amortization expense related to amortizable intangible assets of $27, $32 and $17 for the years ended December 31, 2013, 2012 and 2011, respectively. Amortizable intangible assets are amortized over their estimated useful lives, which range from one to twenty years, using the straight-line method. The Company expects to record annual amortization expense for all existing intangible assets in a range from approximately $21 to $24 from 2014 through 2018.
The changes in net goodwill for the years ended December 31, 2013 and 2012 are as follows:
 
 
 
2013
 
2012
Balance, beginning of year
 
$
691

 
$
466

Acquisitions and divestitures
 
(2
)
 
222

Impact of foreign currency exchange rates
 
2

 
3

Balance, end of year
 
$
691

 
$
691



Acquisition and divestiture activity during the current period is related to the finalization of purchase accounting for certain acquisitions as well as the writeoff of goodwill associated with the sale of the net assets of SAGE Labs in April 2013.

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