11.      CONTINGENCIES, COMMITMENTS, AND GUARANTEES

Royalties

Pursuant to various license agreements, the Company is obligated to make payments based both on the achievement of certain milestones and a percentage of revenues derived from the licensed technology and royalties on net sales.

Employee benefit plan

Under a defined contribution plan available to permanent employees, the Company is committed to matching employee contributions up to limits set by the terms of the plan, as well as limits set by U.S. tax authorities. The Company’s matching contributions to the plan totaled $0.2 million for each of the three year ended December 31, 2014, 2013 and 2012. There were no changes to the plan during the year ended December 31, 2014.

Lease obligations — operating leases

The Company is committed to annual minimum payments under operating lease agreements for its office and laboratory space and equipment) as follows (in thousands):

Rental expense for operating leases in the amount of $0.5 million has been recorded in the consolidated statements of operations for each of the years ended December 31, 2014, 2013 and 2012, respectively. In May 2008, the Company entered into a lease agreement to lease office and laboratory space for its headquarters in Seattle, Washington totaling approximately 17,000 square feet. The lease, which expires in December 2018, provides for a monthly base rent of $47,715 increasing to $52,259 in 2018. The Company has also entered into operating lease obligations through July 2017 for certain office equipment, which are included in the table above.

Guarantees

In the normal course of operations, the Company indemnifies counterparties in transactions such as purchase and sale contracts for assets or shares, service agreements, director/officer contracts and leasing transactions. These indemnification agreements may require the Company to compensate the counterparties for costs incurred as a result of various events, including environmental liabilities, changes in (or in the interpretation of) laws and regulations, or as a result of litigation claims or statutory sanctions that may be suffered by the counterparties as a consequence of the transaction. The terms of these indemnification agreements vary based upon the contract, the nature of which prevents the Company from making a reasonable estimate of the maximum potential amount that could be required to pay to counterparties. Historically, the Company has not made any significant payments under such indemnification agreements and no amounts have been accrued in the accompanying condensed consolidated financial statements with respect to these indemnification guarantees.