Off topic, but reminded me of a great joke from Judge Kozinski in the Roomates.com case, viz.:

". . . Some subscribers are just looking for someone who will get along with their significant other[34] or with their most significant Other.[35]"

[34] "The female we are looking for hopefully wont [sic] mind having a little sexual incounter [sic] with my boyfriend and I [very sic]."

http://scholar.google.com/scholar_case?q=521+F.3d+1157&h...

I think the [very sic] referred to the fact that it should be "my boyfriend and me." That's all.

Practical solution: remove the "sic" and replace it with a "..." to indicate that you've excised a portion of the quote. Or, y'know, don't bother to quote the passage with the offending "sic" at all. You could even come up with a way to phrase it so that you're quoting the original rather than quoting the quotation.

If you wanted to include it and do it unambiguously you'd need to come up with a convention and state it clearly in the text. "Please note that all instances of "[sic]" which use square brackets are author B's insertion when he quoted author A, while instances of "(sic)" with parentheses are my own insertion in quoting author B."

Thus we have "a letter from me [sic] (sic) to you".

You use escaping of course:

    ...suppose I write a letter from me \[sic\] [sic] to you.

Ok, but imagine for a moment that you use the wrong-facing slash like so:

    ...suppose I write a letter from me /[sic/] [sic] to you.

What now, huh?

    ...suppose I write a letter from me /[sic]\[sic\]/[sic] \[sic\] to you

It's turtles all the way down...

Is that sic slash fic?

This is also the solution to the old "putting a smiley emoticon in a parenthesised piece of text".

"(What a good idea :)" evidently needs a second parenthesis. "(What a good idea :))" looks weird and is ambiguous. "(What a good idea :\))" unambiguous: the non-functional parenthesis is escaped.

Unless you're making a point about the [sic], Just remove it. It adds no value and distracts from the original message.

Fun question =)

Yes, I think 2 negatives make a positive here, and the situation where you do want to draw attention to a misplaced [sic] is so rare that it warrants further discussion in your text.

Based on some investigation in Google Books, what books actually do is use a footnote: "blah blah [sic] blah" 1

1 [sic] in original.

It's fundamentally the same thing as clarifying "blah blah blah" (emphasis added) or (emphasis in original).

Note that the purpose of [sic] is not to point out how clever you are to find an error, but to clarify for the reader that the text is copied accurately. Thus, the original question about putting a [sic] on a mistaken [sic] is not something that makes sense to do.

Unless your actual aim is to draw attention to the incorrect use of [sic], when would this actually be needed? Surely the normal use would be "So and so is quoted in the <whatever source> as saying:" in which case you can quote what they said without needing any editorial additions, such as [sic], that the source added themselves.

Their [sic] will look like yours, though. And since it's stipulated that the quotee used [sic] incorrectly, you (the quoter) will look as if you are using it incorrectly.

Happily, readers aren't fragile parsers, demanding escaping or special formatting. They can handle you making your meaning explicit, either inline or in a footnote.

Note beforehand or in brackets at the end that the [sic] was not added - wherever you'd add "emphasis mine" if you'd highlighted part of it.

Italicize the quote or set it in different font. If that is not possible (because of strict style guidelines, maybe), your best remaining option is to lampshade its appearance.

That's what you call a "meta sic".