On January 15, 2009, the Company entered into an "Exclusive Patent and Know-How License Agreement Including Transfer of Ownership" with the Energy and Environmental Research Center Foundation, a non-profit entity ("EERCF"). Under the terms of the Agreement, the Company has been granted an exclusive license by EERCF for the technology to develop, make, have made, use, sell, offer to sell, lease, and import the technology in any coal-fired combustion systems (power plant) worldwide and to develop and perform the technology in any coal-fired power plant in the world. Amendments No. 4 and No. 5 to this agreement were made effective as of December 16, 2013 and August 14, 2014, respectively, expanding the number of patents covered, eliminated certain contract provisions and compliance issues and restructured the fee payments and buyout provisions while granting EERCF equity in the Company. This agreement now applies to 25 domestic and foreign patents and patent applications.

The Company paid EERCF $100,000 in 2009 for the license to use the patents and at the option of the Company can pay $2,500,000 and issue 875,000 shares of common stock for the assignment of the patents or pay the greater of the license maintenance fees or royalties on product sales for continued use of the patents. The license maintenance fees are $25,000 due monthly beginning in January 1, 2014 and continuing each month thereafter. The running royalties are $100 per one megawatt of electronic nameplate capacity and $100 per three megawatt per hour for the application to thermal systems to which licensed products or licensed processes are sold by the Company, associate and sublicensees. Running royalties are payable by the Company within 30 days after the end of each calendar year to the licensor and may be credited against license maintenance fees paid. There were no royalties due for 2015 or 2014.

The Company is required to pay EERCF 35% of all sublicense income received by the Company, excluding royalties on sales by sublicensees. Sublicense income is payable by the Company within 30 day after the end of each calendar year to the licensor. This requirement ends at the time the Company pays for the assignment of the patents. There was no sublicense income in 2015 or 2014.

License costs capitalized as of December 31, 2015 and 2014 are as follows:

The Company is currently amortizing its license to use EERCF's patents over their estimated useful life of 17 years when acquired. During the period ended December 31, 2015 and 2014, amortization expense charged to operations was $5,882 and $5,882, respectively. Estimated amortization for each of the next five years is approximately $5,900.