15. Benefit plans

The Company established a defined contribution savings plan under Section 401(k) of the Code. This plan covers substantially all employees who meet minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre-tax basis. Prior to 2019, matching contributions to the plan were made at the discretion of the Company’s management. Beginning in 2019, the Company provides matching contributions equal to fifty percent (50%) up to six percent (6%) of each participant’s salary. Employees are immediately and fully vested in the Company’s contribution. During the years ended December 31, 2021 and 2020, the Company contributed $0.2 million and $0.1 million to the plan, respectively.