X0306 4 2017-05-10 0 0001078075 NETSCOUT SYSTEMS INC NTCT 0001232884 SZABADOS MICHAEL C/O NETSCOUT SYSTEMS, INC. 310 LITTLETON ROAD WESTFORD MA 01886 0 1 0 0 Chief Operating Officer Common Stock 2017-05-10 4 S 0 5000 34.726 D 38257 D The shares of Common Stock were sold pursuant to a 10b5-1 plan. The shares sold on this date were sold in multiple transactions. This price is the weighted average sales price per share; the actual sales price per share ranged from $34.55 to $34.90. The reporting person undertakes to provide to NetScout Systems, Inc., any security holder of NetScout 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 (2) to this Form 4. /s/ Scott Hodgdon, by Power of Attorney 2017-05-11