Restructuring Charges

During the quarter ended September 30, 2017, we ceased use of 25,812 square feet of our 108,743 square foot headquarters facility located in Waltham, Massachusetts. We recorded a lease obligation charge of $3.1 million. The lease obligation charge comprised of restructuring expense, including sublease income and construction costs, net of deferred rent liabilities of $2.6 million. Additionally, we wrote-off $0.5 million of lease-hold improvements related to the space. In order to estimate the lease obligation charges included in the restructuring expense, we made certain assumptions, including the time period it will take to obtain a subtenant, construction costs, and certain sublease rates. These estimates may vary from the sublease agreements ultimately executed, if at all, resulting in an adjustment to the charges. The restructuring charge was recorded as restructuring expense in the consolidated statements of operations for the three and nine months ended September 30, 2017.

In the first quarter of fiscal 2018, we updated our assumptions, as we had signed a sublease agreement for a portion of the ceased use space and updated our estimates for the expected time period it will take to obtain a subtenant for the remainder of the cease use space. This resulted in an additional $0.5 million of restructuring charges in the first quarter of fiscal 2018.

The following table presents the change in restructuring liability from December 30, 2017 to March 31, 2018 (in thousands):



	March 31, 2018
	Restructuring Liability
Balance as of December 30, 2017	$	3,494
Restructuring charges	187
Payments	(21		)
Changes in estimate	258
Accretion of sublease liability	(279		)
Balance as of March 31, 2018	$	3,639