Income Taxes

The following table provides details of income taxes for the three months ended March 31, 2016 and 2015 (in thousands, except percentages):



	Three months ended
	March 31,
	2016			2015
Loss before provision for income taxes	$	(3,835	)	$	(1,250	)
Provision for income taxes	61			50
Effective tax rate	(2		)%	(4		)%

The effective tax rate fluctuates based on the amount of pre-tax income or loss generated in the various jurisdictions where we conduct operations and pay income tax. The income tax expense of $0.1 million on our pre-tax loss of $3.8 million and $1.3 million for the three months ended March 31, 2016 and 2015, respectively, is primarily due to state minimum income taxes that do not benefit from our state net operating loss carryforwards.

As of December 31, 2015, MRV had federal, state, and foreign net operating loss ("NOL") carryforwards available of $182.5 million, $97.1 million and $97.4 million, respectively. Under the Internal Revenue Code, if a corporation undergoes an "ownership change," the corporation's ability to use its pre-change NOLs, capital loss carryforwards and other pre-change tax attributes to offset its post-change income may be limited. An ownership change is generally defined as a greater than 50% change in its equity ownership by value over a three-year period. We may experience an ownership change in the future as a result of subsequent shifts in our stock ownership. If we were to trigger an ownership change in the future, our ability to use any NOLs and capital loss carryforwards existing at that time could be limited. As of March 31, 2016, the federal, state and foreign NOLs had a full valuation allowance.

On January 26, 2016, the Company's Board of Directors approved the adoption of a "Rights Plan" in an effort to protect the Company from potential adverse consequences arising from an ownership change under the Internal Revenue Code, such adverse consequences including a significant reduction in the annual utilization of the Company’s net operating loss carryforwards and built-in losses. The Rights Plan has not yet been ratified by the stockholders of MRV.