Note 13. Indebtedness

At December 31, 2013, our outstanding indebtedness, and at December 31, 2012, our and SIR's (when SIR was a consolidated subsidiary of ours) outstanding indebtedness, included the following:

	December 31,

	2013		2012
Unsecured revolving credit facility, due October 2015, at LIBOR plus a premium	$	235,000	$	297,000
Unsecured revolving credit facility, due March 2016, at LIBOR plus a premium⁽¹⁾		—		95,000
Unsecured term loan, due December 2016, at LIBOR plus a premium		500,000		500,000
Unsecured term loan, due July 2017, at LIBOR plus a premium⁽¹⁾		—		350,000
Senior Notes, due 2014 at 5.75%		—		244,655
Senior Notes, due 2015 at 6.40%		33,440		186,000
Senior Notes, due 2015 at 5.75%		138,773		250,000
Senior Notes, due 2016 at 6.25%		139,104		400,000
Senior Notes, due 2017 at 6.25%		250,000		250,000
Senior Notes, due 2018 at 6.65%		250,000		250,000
Senior Notes, due 2019 at 7.50%		125,000		125,000
Senior Notes, due 2020 at 5.875%		250,000		250,000
Senior Notes, due 2042 at 5.75%		175,000		175,000
Mortgage Notes Payable, due 2014 at 4.95%		12,040		12,356
Mortgage Notes Payable, due 2015 at 5.99%		7,987		8,272
Mortgage Notes Payable, due 2015 at 5.78%⁽²⁾		—		8,980
Mortgage Notes Payable, due 2016 at 5.235%		116,000		116,000
Mortgage Notes Payable, due 2016 at 5.689%⁽¹⁾		—		7,500
Mortgage Notes Payable, due 2016 at 5.76%		—		7,474
Mortgage Notes Payable, due 2016 at 6.03%		40,334		40,854
Mortgage Notes Payable, due 2016 at 6.29%		144,522		146,264
Mortgage Notes Payable, due 2016 at 7.36%		10,804		11,302
Mortgage Notes Payable, due 2017 at 5.67%		41,275		41,275
Mortgage Notes Payable, due 2017 at 5.68%		265,000		265,000
Mortgage Notes Payable, due 2017 at 5.95%⁽¹⁾		—		18,447
Mortgage Notes Payable, due 2019 at LIBOR plus a premium⁽³⁾		173,247		174,870
Mortgage Notes Payable, due 2021 at 5.69%		28,391		28,793
Mortgage Notes Payable, due 2021 at 5.30%		39,598		40,185
Mortgage Notes Payable, due 2022 at 6.75%		3,456		3,759
Mortgage Notes Payable, due 2023 at 6.14%⁽²⁾		—		12,650
Mortgage Notes Payable, due 2026 at 5.71%		7,240		7,637


		2,986,211		4,324,273
Unamortized net premiums and discounts		19,199		25,548


	$	3,005,410	$	4,349,821

⁽¹⁾: Represents indebtedness of SIR when SIR was a consolidated subsidiary of ours.
⁽²⁾: These mortgage notes are included in liabilities related to properties held for sale at December 31, 2013. See Note 4 for additional information regarding our properties held for sale.
⁽³⁾: Interest on this loan is payable at a spread over LIBOR but has been fixed for the first seven years to December 1, 2016 by a cash flow hedge which sets the rate at approximately 5.66%.

Prepayments:

In March 2013, we purchased a total of $670,295 of the outstanding principal amount of the following senior notes for $726,151, excluding transaction costs, pursuant to a tender offer:

Senior Note	Principal		Purchase Price

5.75% Senior Notes due February 15, 2014	$	145,612	$	148,746
6.40% Senior Notes due February 15, 2015		152,560		164,140
5.75% Senior Notes due November 1, 2015		111,227		121,047
6.25% Senior Notes due August 15, 2016		260,896		292,218


	$	670,295	$	726,151

In connection with the purchase of these senior notes, we recognized a combined loss on early extinguishment of debt totaling $60,027, which includes the write-off of unamortized discounts and deferred financing fees and expenses.

In October 2013, we prepaid at par all $99,043 of our 5.75% unsecured senior notes due 2014, using borrowings under our revolving credit facility. In addition, we prepaid $7,093 of 5.76% mortgage debt in December 2013, in connection with the sale of the related property. In connection with the prepayment of mortgage debt, we recorded a loss on early extinguishment of debt totaling $1,011 from a prepayment premium and the write off of unamortized discount.

Unsecured Revolving Credit Facility and Unsecured Term Loan:

We have a $750,000 unsecured revolving credit facility that is available for general business purposes, including acquisitions. The maturity date of our revolving credit facility is October 19, 2015 and, subject to the payment of an extension fee and meeting certain other conditions, includes an option for us to extend the stated maturity date of our revolving credit facility by one year to October 19, 2016. In addition, our revolving credit facility includes a feature under which maximum borrowings may be increased to up to $1,500,000 in certain circumstances. Borrowings under our revolving credit facility bear interest at LIBOR plus a premium, which was 150 basis points as of December 31, 2013 and 2012. We also pay a facility fee of 35 basis points per annum on the total amount of lending commitments under our revolving credit facility. Both the interest rate premium and the facility fee are subject to adjustment based upon changes to our credit ratings. As of December 31, 2013 and 2012, the interest rate payable on borrowings under our revolving credit facility was 1.7%. The weighted average interest rate for borrowings under our revolving credit facility was 1.7% and 1.5% for the years ended December 31, 2013 and 2012, respectively. As of December 31, 2013, we had $235,000 outstanding and $515,000 available under our revolving credit facility.

We also have a $500,000 unsecured term loan that matures in December 2016 and is prepayable without penalty at any time. Our term loan includes a feature under which maximum borrowings may be increased to up to $1,000,000 in certain circumstances. Our term loan bears interest at a rate of LIBOR plus a premium, which was 185 basis points as of December 31, 2013 and 2012. The interest rate premium is subject to adjustment based upon changes to our credit ratings. As of December 31, 2013 and 2012, the interest rate for the amount outstanding under our term loan was 2.0% and 2.1%, respectively. The weighted average interest rate for the amount outstanding under our term loan was 2.0% and 1.8% for the years ended December 31, 2013 and 2012, respectively.

Our revolving credit facility agreement and our term loan agreement provide for a right to accelerate payment of all amounts due thereunder upon the occurrence and continuation of certain events of default, including a change of control of us and RMR ceasing to act as our business manager and property manager, unless waived by our lenders holding two-thirds of the aggregate credit exposure under the applicable agreement. If the Related/Corvex consent solicitation is successful in removing our entire Board of Trustees, such removal would constitute an event of default under our revolving credit facility and term loan agreements. Either such default, unless waived, would give either the administrative agent or the lenders holding 51% of the aggregate credit exposure under the applicable agreement the right to accelerate payment of all amounts we may owe under such agreement. Such events may also constitute an event of default under certain of our mortgage loans and may trigger cross default provisions of our public debt indenture and related supplements. Related/Corvex have publicly stated that if their consent solicitation is successful in removing our entire Board of Trustees, they will offer to buy 51% of the debt outstanding under our revolving credit facility and term loan agreements at par value to prevent the acceleration of such loans. However, waivers of these defaults under our revolving credit facility and term loan agreements require the approval of the holders of two-thirds of the aggregate credit exposure under the applicable agreement. We can provide no assurance that, in such event, Related/Corvex will be successful in buying any of our outstanding debts or credit commitments, preventing any demand for the immediate payment of these loans or procuring waivers of any default that may be required for the Company to continue to pay dividends or other distributions or repurchase shares. The lenders under these agreements may not be willing to waive any event of default particularly if we have no Trustees.

Credit Facility and Term Loan Debt Covenants:

Our public debt indenture and related supplements, our revolving credit facility agreement and our term loan agreement contain a number of financial and other covenants, including covenants that restrict our ability to incur indebtedness or to make distributions under certain circumstances and require us to maintain financial ratios and a minimum net worth. At December 31, 2013, we believe we were in compliance with all of our respective covenants under our public debt indenture and related supplements, our revolving credit facility and our term loan agreements.

At December 31, 2013, 13 of our continuing properties (18 buildings) costing $1,269,185 with an aggregate net book value of $1,109,259 secured mortgage notes totaling $914,510 (including net premiums and discounts) maturing from 2014 through 2026. In addition, we had mortgage debt secured by two properties (three buildings) classified as held for sale totaling $20,018 (including net premiums and discounts).

The required principal payments due during the next five years and thereafter under all of our outstanding debt at December 31, 2013, excluding principal payments totaling $20,402 for mortgage debt related to properties classified as held for sale, are as follows:


2014	$	18,826
2015		421,821
2016		948,708
2017		560,592
2018		254,614
Thereafter		781,650


	$	2,986,211