! for not matching bash regex

[Lahntaler]

In a bash-script, only the case if a regular expression does not match is relevant. Therefore I used the exclamation mark !. But where to place it?
These two work fine, but are they equivalent?

if ! [[ $abc =~ $pattern ]]; then

or

if [[ ! $abc =~ $pattern ]]; then

Where is the ! placed more correct?

[ianr richmond]

if [[ ! is the syntax I find in the linux startup scripts, from which I have always copied syntax. There are a lot of ways to write, but I look to them for the correct conventions.

[Manko10]

[ is just an executable like test (/usr/bin/[) so in the first example you negate the whole evaluation and in the second example just that one expression, so they are not really equivalent.
Compare these two cases:

if ! [ true -o true  ]; then
    echo 'x'
fi

vs.

if [ true -o ! true  ]; then
    echo 'x'
fi

The first outputs nothing because the expression is true and completely negated; the second outputs "x" because only the second operand of the expression is negated (true OR not true is still true).