Form K restriction

Hi,
I am looking to buy a property with a restriction: No disposition of the registered estate is to be registered without a certificate signed by the applicant for registration or his conveyancer that written notice of the disposition was given to [firm] at [Address] being the person with the benefit of an interim charging order on the beneficial interest of [proprietor] made by [county court] on[date] (case number:[]).
I believe this is a form K restriction. The proprietor is deceased. The seller is not aware of this restriction and no information can be obtained as the financial firm no longer exist. 
I understand that the seller's solicitor can apply to get this restriction removed once notice has been given regarding the sale of the property to the financial firm holding an interim charge. 
Can you please advice on the steps to follow in order to get to exchange?

Many thanks

Hi Sophie - the restriction wording itself explains what's required, namely the creditor as named on the register is notified of the disposition (sale-purchase). See PG 76 section 4 for guidance 
If the seller wanted to apply to cancel the restriction prior to the sale completing then they would need to do so using form RX3 along with supporting evidence to confirm that the protected interest is no more. 
We can't advise you on when to exchange/complete and would recommend you speak to your conveyancer and reference PG 76 

Thank you for your reply. 

Notice of sale was served to the creditor as per the address on the land registry title. However, the firm no longer exist. 
When completing the RX3 form, apart from proof of notice being served what other evidence would typically be required from Land registry in order to remove this restriction? 

Many Thanks

Sophie - notice of the sale should be issued as part of the sale/purchase process to show that the restriction has been complied with, the charging order has been overreached, the form K can be cancelled and that the purchase can then be registered. 
You appear to be missing that process up with the one whereby a seller might apply to cancel the restriction before the purchase completes. Notifying the creditor of the sale would not be sufficient to remove cancel the restriction using form RX3. You would need evidence from the creditor confirming the debt has been paid or the court has dismissed their order.
PG 76 section 4 explains how a form K restriction will be automatically cancelled. No form RX3 is required in the scenario described therein

So my understanding is that we won't need to get the restriction removed (with form RX3) in order to get the purchase registered and title transferred. 

One last question if I may, under this form K restriction who should give notice and signed certificate, is it the seller’s solicitor or the buyer's solicitor? 

Many thanks 

Sophie - correct but you must rely on your conveyancer here as they (or your mortgage lender - if there is one) may decide otherwise. But PG 76 should help.
Who notifies the creditor is up to the conveyancer's involved. But it's the applicant (purchaser) or their conveyancer who give the certificate to confirm that it's been done. So I'd have thought it would be the buyer's conveyancer who sends the notification so that they can give the certificate. But it can be the seller's conveyancer just as long as they can satisfy the other conveyancer that they did actually do it 

Thank you for your prompt reply. That is really helpful in understanding the process.

Many thanks again