The following table presents information about our financial assets and financial liabilities measured at fair value on a recurring basis as of March 31, 2015, and indicates the fair value hierarchy of the valuation techniques utilized by us to determine such fair value. In general, fair values determined by Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities that we have the ability to access. We classify money market funds and United States Treasuries as Level 1 assets.

 

Fair values determined by Level 2 inputs utilize inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. Level 2 inputs include quoted prices for similar assets and liabilities in active markets, and inputs other than quoted prices that are observable for the asset or liability, such as interest rates and yield curves that are observable at commonly quoted intervals. We obtain the fair value of Level 2 financial instruments from a third-party professional pricing service using quoted market prices for identical or comparable instruments. Our professional pricing service gathers market prices from a variety of industry standard data providers, security master files from large financial institutions and other third-party sources. The service uses these multiple prices as inputs into a distribution-curve based algorithm to determine a fair value. We then validate the quoted fair values provided by the professional pricing service by comparing the service’s assessment of the fair values of our Level 2 investment portfolio balance against the fair values of our Level 2 investment portfolio balance provided by our investment managers. We classify United States government agency securities and corporate note holdings as Level 2 assets. There were no transfers between Level 1 and Level 2 during the three months ended March 31, 2015 or 2014.

Level 3 inputs are unobservable inputs for the asset or liability, and include situations where there is little, if any, market activity for the asset or liability. In certain cases, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, the level in the fair value hierarchy within which the fair value measurement in its entirety falls has been determined based on the lowest level input that is significant to the fair value measurement in its entirety. Our assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to the asset or liability. We do not hold any Level 3 assets.

Assets that have recurring measurements are shown below (in thousands):