X0306 4 2012-08-24 0001180145 Cardiovascular Systems Inc CSII 0001304318 Martin David 651 CAMPUS DRIVE ST. PAUL MN 55112 1 1 0 0 President and CEO Common Stock 2012-08-24 4 S 0 862 9.0297 D 359068 D Common Stock 2012-08-27 4 G 0 4200 0 D 354868 D Common Stock 2012-08-27 4 G 0 1400 0 A 1400 I By child Common Stock 2012-08-27 4 G 0 1400 0 A 1400 I By child Common Stock 2012-08-27 4 G 0 1400 0 A 1400 I By child Stock Option (right to buy) 8.83 2016-07-16 Common Stock 71170 71170 D Stock Option (right to buy) 8.83 2016-08-14 Common Stock 38820 38820 D Stock Option (right to buy) 8.83 2017-02-14 Common Stock 349380 349380 D Stock Option (right to buy) 7.90 2017-06-11 Common Stock 90580 90580 D Stock Option (right to buy) 12.15 2017-12-11 Common Stock 242625 242625 D Stock Option (right to buy) 8.75 2019-03-01 Common Stock 32350 32350 D In connection with the vesting and delivery of restricted stock, on each date shares were sold and the net proceeds were used to pay required withholding taxes. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $8.98 to $9.20 inclusive. The reporting person undertakes to provide Cardiovascular Systems, Inc., any security holder of Cardiovascular Systems, Inc. or the staff of the Securities and Exchange Commission upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. This transaction involved a gift of securities by the reporting person to three minor children, who each share reporting person's household. Fully exercisable. /s/ Scott J. Dorfman as Attorney-in-Fact for David L. Martin pursuant to Power of Attorney previously filed. 2012-08-28