According to E! Online, the interior designer - who met Swiderski on the fifth season of the show - must return the gem to ABC under the terms of her contract.
"I do not have any knowledge of Jillian returning her engagement ring to ABC. However, in the event of a break-up of a Bachelor/ette couple, the agreement with the show's producers is to return the ring," said her representative.
"Jillian Harris is one of the most integrous people you can find, and on all accounts I have no doubt she has and will do the honourable thing."
ABC has yet to comment.
Harris and Swiderski confirmed their split earlier this week, with one report saying that Harris is planning to spend some time at her parents' home in Canada.
> 'Bachelorette' Jillian Harris 'avoids negativity'