7. Commitments and Contingencies

Facility Leases

In March 2014, the Company entered into an operating facility lease agreement to lease approximately 12,900 square feet in Menlo Park, California for its new headquarters building for a period of thirty-nine months. The total obligation for the Company under this lease is approximately $1.3 million as of December 31, 2015.

In December 2015, the Company entered into an operating sublease agreement to lease additional office space in Menlo Park for a period of twenty-four months. The lease commencement date is January 1, 2016 and the total obligation of approximately $1.2 million has been excluded from the table below.

Rent expense was $763,000, $520,000, and $241,000 for the years ended December 31, 2015, 2014, and 2013, respectively.

As of December 31, 2015, the aggregate future minimum lease payments under the noncancellable operating lease arrangements are as follows (in thousands):

Year Ended December 31, 2015
2016	$	773
2017		524
2018		—
2019		—
2020		—
Thereafter		—
	$	1,297

Purchase Commitments

The Company conducts research and development programs through a combination of internal and collaborative programs that include, among others, arrangements with contract manufacturing organizations and contract research organizations. The Company had contractual arrangements with these organizations including license agreements with milestone obligations and service agreements with obligations largely based on services performed.

In the normal course of business, the Company enters into various firm purchase commitments related to certain preclinical and clinical studies. At December 31, 2015 the noncancellable portion of these commitments, in aggregate, totaled approximately $2.2 million and is expected to be paid within the next fiscal year.

Contingencies

In the normal course of business, the Company enters into contracts and agreements that contain a variety of representations and warranties and provide for general indemnifications. The Company’s exposure under these agreements is unknown because it involves claims that may be made against the Company in the future, but have not yet been made. The Company accrues a liability for such matters when it is probable that future expenditures will be made and such expenditures can be reasonably estimated.

As of December 31, 2015 the Company is contingently committed to make development and sales-related milestone payments of up to $30.0 million under certain circumstances, and other payments of $10.0 million, as well as royalties relating to potential future product sales under the License Agreement with Amunix. The amount, timing and likelihood of these payments are unknown as they are dependent on the occurrence of future events that may or may not occur, including approval by the FDA of potential drug candidates.

Indemnification

In accordance with the Company’s amended and restated Certificate of Incorporation and amended and restated bylaws, the Company has indemnification obligations to its officers and directors for certain events or occurrences, subject to certain limits, while they are serving at the Company’s request in such capacity. There have been no claims to date and the Company has a director and officer insurance policy that may enable it to recover a portion of any amounts paid for future claims.

Litigation

The Company may from time to time be involved in legal proceedings arising from the normal course of business. There are no pending or threatened legal proceedings as of December 31, 2015.