defensive offside question

[ase]

i was reading tampa bay vs oakland play by play from NFL.com

i have a question about the following play by play

Third Quarter

3-5-OAK44 (:11) B.Johnson pass incomplete to J.White.
4-5-OAK44 (:06) J.Bidwell punts 33 yards to OAK 11, Center-D.Moore, fair catch by P.Buchanon.
PENALTY on OAK-J.Redmond, Defensive Offside, 4 yards, enforced at OAK 44 - No Play.

Fourth Quarter
Tampa Bay Buccaneers continued...
4-1-OAK40 (15:00) B.Johnson up the middle to OAK 39 for 1 yard (D.Clark).

1-10-OAK39 (14:34) B.Johnson pass to T.Brown to OAK 32 for 7 yards (N.Harris, T.Smith).

4th down and five, how come a defensive offside only penalize oakland for 4 yards not 5 yards? i thought it is 5 yards for defensive offside and give tampa bay a first down?