Caitlyn Jenner's 'Jenner Skincare' could confuse customers into believing the rest of the family were associated with the products. (Photo by Evan Agostini/Invision/AP, File)
Caitlyn Jenner has had a number of trademark applications rejected because of her famous name as they were too similar to those already registered by ex-wife Kris Jenner and their daughters Kendall and Kylie Jenner.

The 'I Am Cait' star had applied to register 'Jenner Skincare' and 'Skincare By Jenner', but has received a letter from the US Patent & Trademark Office (USPTO), which stated they were too similar to monikers already registered by her ex-wife Kris Jenner and their children Kylie and Kendall Jenner.

The USPTO office made it clear that 'Jenner Skincare' could confuse customers into believing the rest of the family were associated with the products, especially because so many of Kris and her daughters' registered trademarks are connected with beauty and skincare, citing 'Kylie Cosmetics by Kylie Jenner' as one example. 

And the trademark attorney told Caitlyn that her proposed name was too similar to that of her ex-wife's.

However, officials gave the 69-year-old former Olympian the greenlight to use 'Caitlyn Jenner Skincare' and 'Skincare By Caitlyn Jenner' because there was no scope for confusion.

Since transitioning, Caitlyn has become estranged from her ex Kris and her former stepchildren - including famous sister trio Kim, Khloe, and Kourtney Kardashian, and their brother Rob Kardashian - after passages in her 2017 memoir created a rift between them, with the Kardashians claiming their former stepfather had unfairly slammed their mother.

But Caitlyn still speaks warmly of the 'Keeping Up with the Kardashians' stars, as she still counts them as her children, and says they've all "done so extremely well" in their lives.

She said: "Kimberly has been out there and she's extremely smart - all my kids [are]. I have 10 kids and 14 grandchildren. All my kids have done so extremely well. The ones you don't even see on camera are very successful. 

"I'm so proud of my family ... They are very entrepreneurial. All of them. They've done very well for themselves. They've used their celebrity status and the show to build businesses to be out there in the marketplace."