People.com said the 36-year-old model got permission for the name change Friday from a Los Angeles commissioner, more than four years after she married the British singer, whose full name is Seal Henry Olusegun Olumide Adeola Samuel.
Klum appeared in the Victoria's Secret lingerie fashion show in New York this week, six weeks after giving birth to the couple's fourth child.
Klum's unidentified representative told People magazine it remains unclear if the "Project Runway" host will use Heidi Samuel as her professional name.
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