Your Grammar Nazi

Erik Loomis, whom I hate to call out because I love his writing on labor, the environment and political history, but who should be ashamed of himself for this one:

But it’s membership had been small for decades before that merger.

Here's how that sentence reads without the contraction:

But it is membership had been small for decades before that merger.

Recently PZ Myers showed how to do it right:

Big picture management is by an executive committee. It’s not democratic, because its job is to just get stuff done.

Here's the easy rule: it's (with an apostrophe) is a contraction and always means "it is."  Its  (no apostrophe) is possessive and always refers to something that belongs to it.

Getting its and it's backwards is evidence of illiteracy. You're not illiterate, so get it right.