Goodwill and Other Intangible Assets

The amounts for goodwill and changes in the carrying value by segment for the

three

months ended

March 31, 2018

are as follows:

(a)

The additions resulted from the acquisition of IXYS.

The components of other intangible assets at

March 31, 2018

are as follows:

(in thousands, except weighted average useful life)	Weighted Average Useful Life	Gross Carrying Value		Accumulated Amortization		Net Book Value
Patents, licenses and software	10.6	$	193,622	$	64,012	$	129,610
Distribution network	12.6		44,473		33,434		11,039
Customer relationships, trademarks, and tradenames	18.1		314,452		59,591		254,861
Order backlog	1.0		12,400		2,504		9,896
Total		$	564,947	$	159,541	$	405,406

During the

three

months ended

March 31, 2018,

the Company recorded additions to other intangible assets of

$211.6

million, related to the IXYS acquisition, the components of which were as follows:

(in thousands , except weighted average useful life )	Weighted Average Useful Life	Amount
Patents, licenses and software	8.0	$	51,500
Customer relationships, trademarks,and tradenames	17.2		147,700
Order backlog	1.0		12,400
Total		$	211,600

During the

three

months ended

March 31, 2018

and

April 1, 2017,

the Company recorded amortization expense of

$12.0

million and

$5.9

million, respectively for intangible assets with definite lives.

Estimated annual amortization expense related to intangible assets with definite lives as of

March 31, 2018

is as follows: