Kylie Jenner has explored buying back Coty's $600 million stake in her makeup brand

Kylie Jenner has explored taking back ownership of the cosmetics line she sold to Coty three years ago, according to people familiar with the matter, a sign of how the relationship between one of the world’s largest beauty companies and one of entertainment’s most famous families has become strained.

In recent months, Jenner has had informal discussions…