The Company has entered into lease agreements for office space and research facilities in San Diego County, California; Melbourne, Florida; Scottsdale, Arizona; Taipei, Taiwan; Shenzhen and Jiangsu, China; and Cambridgeshire, United Kingdom. Rent expense was $235,282 and $232,947 for the three months ended March 31, 2019 and 2018, respectively. The longest lease expires in June 2024. The Company moved into its facility in San Diego, California during the year ended December 31, 2014. The San Diego facility lease agreement included a tenant improvement allowance which provided for the landlord to pay for tenant improvements on behalf of the Company up to $515,000. Based on the terms of this landlord incentive and involvement of the Company in the construction process, the leasehold improvements purchased under the landlord incentive were determined to be property of the Company.

The future minimum lease payments required under operating leases in effect at March 31, 2019 were as follows:

Year ending:
2019 (remaining nine months)	$	781,489
2020		724,744
2021		322,959
2022		104,157
2023		71,897
2024		30,217
	$	2,035,463

In some agreements to which the Company is a party, the Company has agreed to indemnify the other party for certain matters, including, but not limited to, product liability and intellectual property. To date, there have been no known events or circumstances that have resulted in any material costs related to these indemnification provisions and no liabilities have been recorded in the accompanying financial statements.