definiens: means the outstanding convertible promissory notes of the Company issued pursuant to the ( a ) that certain Note and Warrant Purchase Agreement, dated May 25, 2018, by and among Lineagen, Inc. and the persons and entities named on the Schedule of Purchasers attached thereto, ( b ) that certain Note and Warrant Purchase Agreement, dated July 19, 2018, by and among Lineagen, Inc. and the persons and entities named on the Schedule of Purchasers attached thereto, ( c ) that certain Note and Warrant Purchase Agreement, dated December 13, 2018, by and among Lineagen, Inc. and the persons and entities named on the Schedule of Purchasers attached thereto and ( d ) that certain Note and Warrant Purchase Agreement, dated February 12, 2019, by and among Lineagen, Inc. and the persons and entities named on the Schedule of Purchasers attached thereto ; as amended by ( i ) that certain Amendment No . 1 to Convertible Promissory Notes, dated November 20, 2018, ( ii ) that certain Omnibus Amendment No . 2 to Convertible Promissory Notes, dated February 12, 2019, ( iii ) that certain Omnibus Amendment No . 3 to Convertible Promissory Notes, dated May 30, 2019, and ( iv ) that certain Omnibus Amendment No . 4 to Convertible Promissory Notes, dated April 15, 2020