[1] At the request of Federal Minister of Labour and Social Affairs Ursula von der Leyen, Heilmann negotiated a high-profile agreement between investor Nicolas Berggruen and other shareholders on the sale of embattled department house chain Karstadt in 2010.

In 2012, Heilmann – together fellow state ministers Mario Czaja and Frank Henkel – unsuccessfully advocated for a reduction in the penalty-free personal use of cannabis from 15 to six grams.

[9] In July 2023, Heilmann made news headlines when the Federal Constitutional Court issued an injunction blocking parliament from considering a plan submitted by the government of Chancellor Olaf Scholz to encourage home owners to replace fossil fuel heating systems with cleaner alternatives.

This way, the court ruled in favor of Heilmann’s emergency petition in which he had argued that his rights as a lawmaker would be violated by it being pushed through without an opportunity for more detailed consideration.

[10][11] Ahead of the Christian Democrats' leadership election in 2018, Heilmann publicly endorsed Annegret Kramp-Karrenbauer to succeed Angela Merkel as the party's chair.