I checked the link I used in my post as well as two more that I came across. All three no longer work; two come up saying the campaign is over. I'm guessing Bic pulled the coupon.
I believe the $1/2 may still be working. While two packages of two pens would no longer be free, the cost for both packages would be about $3. Not a great deal, but not a bad deal for a decent pen at about $.75 each.
The $1/2 coupon may be found here on page 9 without using a zip code: