Refinancing a building's underlying mortgage

Just going by the co-op mortages I've looked at on ACRIS, there's often a prepayment penalty.

"there's often a prepayment penalty. "

There is almost always a prepayment penalty, especially when it's at a higher rate than market. Yield maintenance.

Thanks. Out of curiosity, is there a reason why building mortgages have prepayment penalties, when individual mortgages usually don't?

because they (residential mortgages)) can't, by law, in NY (although some do anyway; there must be some carve outs that they are dancing around). Commercial mortgages (which Coop underlyings are) can have prepayment penalties and almost always do.