6.	Notes Payable

On September 9, 2013, the Company entered into a loan and security agreement with Comerica Bank (“Comerica”), as amended on December 22, 2014, which provided for borrowings of up to $3,000 through August 2014. On September 9, 2013, the Company received $1,000 from borrowings under the agreement, and from March to August 2014, the Company received $2,000 from additional borrowings under the agreement. Through December 31, 2014, the Company borrowed the full $3,000 available under the loan and security agreement and had made $400 of scheduled principal repayments. During the nine months ended September 30, 2015, the Company made $900 of scheduled principal repayments. Borrowings under the loan and security agreement are collateralized by substantially all of the Company’s assets, except for its intellectual property.

In accordance with the terms of the loan and security agreement, the Company is obligated to make monthly, interest-only payments on any term loans funded under the agreement until August 1, 2014. Thereafter, the Company is obligated to pay 30 consecutive, equal monthly installments of principal and interest from September 1, 2014 through February 1, 2017, the maturity date. Term loans under the loan and security agreement bear interest at an annual rate equal to 3.0% plus the greater of (1) the bank’s prime rate and (2) the LIBOR rate plus 2.5%. As of September 30, 2015, the greater rate was 6.25%. In addition, a final payment of $60 is due upon the earlier of the maturity date, acceleration of the term loans or prepayment of all or part of the term loans. That amount is being recorded as additional interest expense over the term of the loan and security agreement, using the effective interest method.

On September 17, 2015, the Company made a payment of $1,765 to Comerica to satisfy all amounts owed under the loan and security agreement. The extinguishment amount was comprised of $1,700 of outstanding principal and $65 of final fees and accrued interest. Upon payment, Comerica released the Company of all security interests held in the Company’s assets, except for the cash collateral securing the Company’s corporate cards and standby letters of credit, and terminated all loan documents related to the loan and security agreement (other than any indemnification obligations and other provisions which survive termination).

In connection with the extinguishment of the loan and security agreement, the Company recorded a loss on extinguishment of $140, which has been recorded as interest expense in the three and nine months ended September 30, 2015.

Accretion of the debt discount recorded as additional interest expense was $73, $96, $16 and $49 for the three and nine months ended September 30, 2015 and 2014, respectively. As of September 30, 2015 and December 31, 2014, the unamortized debt discount was $0 and $96, respectively.