Howard K. Stern lost a big one in the Bahamas today.

Stern's appeal on DNA testing was just rejected, and Howard K. was penalized by the three-judge panel to the tune of $10,000. TMZ has learned Stern was ordered to pay $5,000 in attorney's fees to the Registrar General and $5,000 to Birkhead's lawyer -- not Debra Opri, the Bahamian one.

This could clear the way for the unsealing of the DNA test results -- that should happen in court this week.

Typically, these penalties (called "sanctions") are imposed when an appeal is frivolous.

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