X0303 4 2010-01-11 0001140486 ATHEROS COMMUNICATIONS INC ATHR 0001198046 HENNESSY JOHN L C/O ATHEROS COMMUNICATIONS, INC. 5480 GREAT AMERICA PARKWAY SANTA CLARA, CA 95054 1 0 0 0 Common Stock 2010-01-11 4 S 0 14200 36.18 D 33699 I See Footnote Common Stock 2010-01-11 4 S 0 800 37.10 D 32899 I See Footnote The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan. Represents the weighted average sales price for a number of sale transactions effected at prices ranging from $35.90 to $36.89. The Reporting Person has provided to the issuer, and undertakes to provide upon request by the SEC staff, or any security holder of the issuer, information regarding the number of shares sold at each separate price within the range. Represents the weighted average sales price for a number of sale transactions effected at prices ranging from $36.93 to $ 37.26. The Reporting Person has provided to the issuer, and undertakes to provide upon request by the SEC staff, or any security holder of the issuer, information regarding the number of shares sold at each separate price within the range. By the 1993 Hennessy Revocable Trust Bruce P. Johnson, Attorney-in-fact 2010-01-12