This has come up on this board a number of times in the past. In September of 2005, I contacted Chipco and asked if this type of chip was an error, sample, or something else. I received this reply:

Lee,
The chips you asked about have been confirmed as samples only. These are
not error chips.
Thanks
Jodi Cooper
Sales Service

I've been told that years ago Chipco passed these chips out "like candy" (in large quantities).