a <- c("id1234|a; b; c; d",
"id5678|a; b; e; f",
"id9012|a; g; h; i",
"id3456|a; j; k; l")
sub("^[^|]*\\|([^;]*;[^;]*).*", "\\1", a)
## => [1] "a; b" "a; b" "a; g" "a; j"
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