X0306 4/A 2012-09-07 2012-09-11 0 0001023313 FORRESTER RESEARCH INC FORR 0001353190 Rutstein Charles C/O FORRESTER RESEARCH 60 ACORN PARK DRIVE CAMBRIDGE MA 02140 1 1 0 0 Chief Operating Officer Common Stock 2012-09-07 4 M 0 9144 21.87 A 11269 D Common Stock 2012-09-07 4 S 0 9144 30.79 D 2125 D Common Stock 2012-09-07 4 M 0 5643 25.25 A 7768 D Common Stock 2012-09-07 4 S 0 5643 30.79 D 2125 D Common Stock 2012-09-10 4 M 0 3690 25.25 A 5815 D Common Stock 2012-09-10 4 S 0 3090 30.75 D 2725 D Common Stock 2012-09-10 4 S 0 600 30.60 D 2125 D Incentive Stock Option 21.87 2012-09-07 4 M 0 9144 0.00 D 2010-02-15 2016-04-14 common stock 9144 0 D Non Qualified Stock Option (Right to Buy) 25.25 2012-09-07 4 M 0 5643 0.00 D 2012-04-01 2019-06-30 common stock 5643 9357 D Non Qualified Stock Option (Right to Buy) 25.25 2012-09-10 4 M 0 3690 0.00 D 2012-04-01 2019-06-30 common 3690 5667 D Two amendments were made to the original Form 4: (i) the Expiration Date for the second transaction in Section 6 of Table II was corrected from 06/30/2012 to 06/30/2019; and (ii) a third row was added in Table II to reflect that the transaction originally reported as having occurred on 09/07/2012 for 9333 shares, actually occurred on 09/07/2012 with respect to 5643 shares and 09/10/2012 with respect to 3690 shares. Maite Garcia, attorney-in-fact for Charles Rutstein 2012-09-13