^start of line
Negative Lookahead(?!666|000) Negative Lookahead(?!219-09-9999|078-05-1120) 1st Alternative219-09-9999 219-09-9999the literal text 219-09-9999 2nd Alternative078-05-1120 078-05-1120the literal text 078-05-1120 0-8one character from 0 (4810) to 8 (5610)
\d{2}a digit, repeated exactly 2 times
-the literal - (4510 / 558 / 2D16)
\da digit
1-9one character from 1 (4910) to 9 (5710)
-the literal - (4510 / 558 / 2D16)
Negative Lookahead(?!0{4}) 0{4}the literal 0 (4810 / 608 / 3016) , repeated exactly 4 times
\d{3}a digit, repeated exactly 3 times
1-9one character from 1 (4910) to 9 (5710)
$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