Steve,
  Some companies/people want non marked chips to hinder benchmarking or coping of the design of
the circuitry.   One such design I've seen was for a DSS card reprogrammer that was purchase
through a hackers net.  I think the individuals who were selling the cards felt that if your bold
enough to be reprogramming your DDS card for free pay TV, you might just be inclined to copy
their reprogrammer design.  Silkscreen or Black Epoxy can be removed if needed.

CDS

Stephen R. Gregory wrote:

> Edwin,
>
>      I must say, I see a lot of posts from others about how to prevent I.C.
> markings from coming off during the assembly process, but yours has to be the
> first one I've seen asking how to remove the marking...are you sure you want
> to do that?
>
>      I just say that because I know there was a big stink a while back about
> some "shady" companies re-marking parts to indicate that they performed faster
> than they actually were...I'm not insinuating that you are doing that, but it
> is unusual that one would want to remove the permanent marking from a IC.
>
>      But to give you some info, instead of removing the marking, why not cover
> it? A silkscreen and some black epoxy ink works just fine...
>
>                               -Steve Gregory-
>
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