The Company leases facilities under non‑cancelable operating leases. Rent expense was $1.7 million and $2.1 million for the years ended December 31, 2020 and 2019, respectively.

Future minimum lease payments for operating lease obligations are as follows as of December 31, 2020 (in thousands):

Year Ending December 31,
2021	$	703
2022		724
2023		112
2024		—
2025		—
Thereafter		—
	$	1,539

In April 2014 and amended in October 2016, the Company entered into a worldwide agreement with AVEO to develop and commercialize AVEO's hepatocyte growth factor inhibitory antibody ficlatuzumab with the Company's proprietary companion diagnostic test, BDX004, a version of the Company’s serum protein test that is commercially available to help physicians guide treatment decisions for patients with advanced non‑small cell lung cancer (NSCLC). Under the terms of the agreement, AVEO will conduct a proof‑of‑concept (POC) clinical study of ficlatuzumab for NSCLC in which BDX004 will be used to select clinical trial subjects (the NSCLC POC Trial). The Company and AVEO will share equally in the costs of the NSCLC POC Trial, and each will be responsible for 50% of development and regulatory costs associated with all future clinical trials agreed upon by the Company and AVEO. The Company and AVEO continue to conduct POC clinical trials of ficlatuzumab in combination with BDX004 with each responsible for 50% of development and regulatory costs.

In September 2020, the Company exercised its opt-out right with AVEO for the payment of 50% of development and regulatory costs for ficlatuzumab effective December 2, 2020. The Company had $0.3 million in remaining obligations related to the AVEO agreement as of the opt-out date. Following the effective date, the Company is entitled to a 10% royalty of net sales of ficlatuzumab and 25% of license income generated from the licensing of ficlatuzumab from AVEO.

Expenses related to this agreement for the years ended December 31, 2020 and 2019 were approximately $0.9 million and $0.9 million, respectively.

In August 2019, we entered into a non-exclusive license agreement with Bio-Rad Laboratories, Inc. (Bio-Rad) (the Bio-Rad License). Under the terms of the Bio-Rad License, the Company received a non-exclusive license, without the right to grant sublicenses, to utilize certain of Bio-Rad’s intellectual property, machinery, materials, reagents, supplies and know-how necessary for the performance of Droplet Digital PCR™ (ddPCR) in cancer detection testing for third parties in the United States. The Company also agreed to purchase all of the necessary supplies and reagents for such testing exclusively from Bio-Rad, pursuant to a separately executed supply agreement (the Supply Agreement) with Bio-Rad. As further consideration for the non-exclusive license, the Company agreed to pay a royalty of 2.5% on the net revenue received for the performance of such ddPCR testing collected from third parties. The Bio-Rad License expires in August 2024. Either party may terminate for the other’s uncured material breach or bankruptcy events. Bio-Rad may terminate the Bio-Rad License if the Company does not purchase licensed products under the Supply Agreement for a consecutive twelve-month period or for any material breach by us of the Supply Agreement. The Company incurred royalty expense of $0.1 million and $0.1 million for the years ended December 31, 2020 and 2019, respectively, under the Bio-Rad License.

As part of the acquisition of Oncimmune, the Company entered into several agreements to govern the relationship between the parties. The Company agreed to a revenue share payment related to an acquired diagnostic test of 8% of recognized revenue for non-screen tests up to an annual minimum volume and 5% thereafter, with an escalating minimum through the first four years of sales. Revenue share expenses of $0.3 million were recognized for the year ended December 31, 2020.