Tier 2 visa extension- Immigration skills charge query

[Loubell]

Hello,
There is some conflicting advice online. Does anyone know if your employer incurs the immigration skills charge if you are applying from inside the UK to extend your visa?
If they don't have to pay the charge, is the only cost to them assigning the Certificate of Sponsorship?
Thank you in advance!

[poper]

Hello,
There is some conflicting advice online. Does anyone know if your employer incurs the immigration skills charge if you are applying from inside the UK to extend your visa?
No immigration skills charge applies for extensions

If they don't have to pay the charge, is the only cost to them assigning the Certificate of Sponsorship?
yes, and visa fees
Thank you in advance!