X0306 4 2018-07-25 true 0000711772 CAMBRIDGE BANCORP CATC 0001713890 Johnson Thomas Arthur C/O CAMBRIDGE BANCORP 78 BLANCHARD ROAD BURLINGTON MA 01803 false true false false EVP / Consumer Lending Dir Common Stock 2018-07-25 4 J false 592 0 D 15296 D Common Stock 2018-07-25 4 A false 121 0 A 1565 I ESOP Performance Based Restricted Stock Units 2018-07-25 4 J false 1393 0 D 2019-12-31 Common Stock 1393 499 D Performance Based Restricted Stock Units 2018-07-25 4 J false 1465 0 D 2018-12-31 Common Stock 1465 1107 D Performance Based Restricted Stock Units 2018-07-25 4 J false 3979 0 D 2020-12-31 Common Stock 3979 429 D In connection with Mr. Johnson's retirement, effective July 25, 2018, these amounts were forfeited. ESOP share total reflects ESOP allocations and dispositions that have occurred since the last ownership reporting. This PRSU award will vest based upon the Company's average three-year performance relative to the Commercial Bank Peer Group for return on assets ("ROA") and diluted earnings per share ("EPS") growth for the period ending December 31, 2019. Any shares earned will vest upon Compensation Committee certification of performance achievement following completion of the performance period. Amount reflects vesting at target rather than maximum possible amount as previously reported. This PRSU award will vest based upon the Company's average three-year performance relative to the Commercial Bank Peer Group for ROA and diluted EPS growth for the period ending December 31, 2018. Any shares earned will vest upon Compensation Committee certification of performance achievement following completion of the performance period. Amount reflects vesting at target rather than maximum possible amount as previously reported. This PRSU award will vest based upon the Company's average three-year performance relative to the Commercial Bank Peer Group for ROA and diluted EPS growth for the period ending December 31, 2020. Any shares earned will vest upon Compensation Committee certification of performance achievement following completion of the performance period. Amount reflects vesting at target rather than maximum possible amount as previously reported. /s/Michael Carotenuto, as Attorney-in-Fact 2018-07-27