G'day tj999,

Welcome to the Monastery.

Before seeing other responses, my first thought was a lookbehind assertion: 

/(?<=222,)(\d{3})/g

[download]

Having seen other solutions, I think this is clearer than embedding a capture in an assertion.

Here are some tests using your example string and the two others used in earlier replies. 

$ perl -E 'say for "222,222,123" =~ /(?<=222,)(\d{3})/g'
222
123
$ perl -E 'say for "222,345,222,678,222,222,543,111" =~ /(?<=222,)(\d{
+3})/g'
345
678
222
543
$ perl -E 'say for "123,222,456,222,222,111,222,999" =~ /(?<=222,)(\d{
+3})/g'
456
222
111
999

[download]

— Ken

In reply to Re: Shift regex search back 4 characters... by kcott
in thread Shift regex search back 4 characters... by tj999

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