Last time I went to the US the officer in the border wrote a "code" in my passport (picture)... What does it mean?
2 Answers
SPL is the post code for São Paulo, so this may be an annotation identifying the visa under which you were admitted.
A Visa was issued on 28 October 2014 at SPL São Paulo on your other passport numbered K0530692
That's what was indicated.
That visa granted you the right to report at Port of Entry. Due to one of many possible (valid) reasons you were using a different passport to request entry.
SPL 28 OCT 2014 X0530692
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