Ouch! If you're going to use Elizabethan English, at least get the grammar right!
Yes, the English used in Shakespeare's time had rules, too. You can't just write "giveth" wherever you feel like it. It conjugates like this:
- I give
- Thou givest
- He giveth
- We give
- You give
- They give
So "SpamGuard taketh away" is correct (third person singular). But "Spammers giveth" is cringe country. "Spammers" is plural, and must be combined with "give", just like in today's English. At best you could say, "The spammer giveth."
But why would you want to? Why would Yahoo! want to evoke the King James Bible in an ad for e-mail spam blocking? Are they using an algorithm developed by Francis Bacon?
Like, what giveth?