That does not actually contradict what I said, anon. "Or" means either or both can apply--the rule as written means that either "can be found on the first two pages" or "less than a week old" is sufficient to make "do not repost" hold true."

To make it a little easier to understand, consider the sentence "Don't eat snow that is yellow or brown," which is shorter but has the same basic structure. You'd understand that to mean you shouldn't eat snow that is yellow and you shouldn't eat snow that is brown. You wouldn't say it meant "don't eat snow that's both yellow and brown, but if it's only one of the two it's fine."

If the rule is meant to be that it's okay for it to be only one of those things as long as it isn't both of them, then it should say "Do not repost a meme that can be found on the first two pages of Bakerstreet and is less than a week old." Or actually it might be better to rephrase it. "Do not repost a meme unless either it cannot be found on the first two pages of Bakerstreet, or it is at least a week old."