- Hotmail's false positive rate rose from 5.6 % to 9.4% in the third quarter.
- Gmail's false positive rate rose from 4.1% to 7.17% in the third quarter.
Hotmail's increase may be attributed to their Sender ID implementation. Gmail's increase may be due to the fact that the Google engineers are still tweaking the filters. My personal experience I have 1 out of 100 legitament emails a week get labeled as SPAM.
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