X0206 3 2019-05-09 0 0001178697 SONIM TECHNOLOGIES INC SONM 0001270347 WALKER JAMES M 1875 SOUTH GRANT STREET, SUITE 750 SAN MATEO CA 94402 0 1 0 0 Chief Financial Officer Common Stock 38000 D Stock Option (right to buy) 0.90 2028-09-09 Common Stock 201666 D Stock Option (right to buy) 10.94 2029-04-10 Common Stock 75000 D Represents restricted stock units award that vest in four equal annual installments of 25% each beginning on April 10, 2019. Twenty-five percent of the shares subject to the option vests on the first anniversary of the vesting commencement date, and the remainder vests in 36 equal monthly installments thereafter for the following three years. /s/ Taruna Punj, Attorney-in-Fact for James M. Walker 2019-05-09