Chelsea reportedly insisted on a buy-back clause in the deal that took Bertrand Traore to Lyon, while a similar agreement will be reached with Bournemouth for the sale of Nathan Ake.
The Blues offloaded the promising Burkina Faso youngster for an initial fee of around £8.8m, rising to close to double that amount should he hit various performance-related targets.
According to the Daily Mail, a further clause in Traore's contract will see Chelsea receive 15% of any profit Lyon make should they sell him further down the line.
It is claimed that discussions are ongoing with Bournemouth over a similar clause for Ake, who is close to sealing a £20m switch to the south coast after impressing on loan last term.
Chelsea are also looking to bring players in this summer, with Juventus defender Alex Sandro - said to be valued at £61m by Juventus - at the top of their wishlist.
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