^start of line
Negative Lookahead(?!(000|666|9)) 9the literal 9 (5710 / 718 / 3916)
\d{3}a digit, repeated exactly 3 times
-?optionally matches the literal - (4510 / 558 / 2D16)
Negative Lookahead(?!(00)) \d{2}a digit, repeated exactly 2 times
-?optionally matches the literal - (4510 / 558 / 2D16)
Negative Lookahead(?!(0000)) 0000the literal text 0000 \d{4}a digit, repeated exactly 4 times
$end of line
g modifier: global. Finds all matches instead of stopping after the first
m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string