“i.e.” and “e.g.”

These Latin abbreviations are not interchangeable: “i.e.” means only “that is” or “in other words”; “e.g.” means only “for example” (or, for the literati or anyone living two thousand years ago, “id est” and “exempli gratia.”)

The Rule: use “i.e.” when you want to clarify, “e.g.” when you want to illustrate.

So if the phrase following the abbreviation does not illustrate, i.e., if it does not offer an example, use “i.e.”

I did not find a case directly on point, e.g., i.e., where a corporation was subject to personal jurisdiction based on a name change alone.

Most lawyers make the opposite mistake; they write “i.e.” when they mean “e.g.,” e.g.:

Such femur fractures can be caused by a variety of osteoporosis drugs, i.e., e.g., Fosamax, Boniva, Actonel, and Reclast.

Finally:

Always a comma before.

Never a space between.

Sometimes a comma after. (But a comma after is always acceptable, so I would do it automatically.) You may italicize either, but you don’t have to.

“I.e.” and “e.g.” are easy to confuse, but if you remember one thing, the rest follows: “e.g.” means “example.”