Upvote:4
The notation is normally written on top of the CBP stamp that indicates when you were admitted to the US. The stamp has two blank lines, one labeled class and the other labeled until.
The notation indicates that you were admitted in B-2 status ("class"), until the 13th of February, 2014. That notation concerns only your first entry. After you leave the US, when you enter the next time, you'll get a new stamp with a new "until" date. With each entry, the class will either be B1 or B2, depending on the purpose of that trip as described to the immigration officer.