Celebrity talent spotter Simon Cowell is facing a multimillion-dollar High Court legal claim in London brought by his former business adviser Ian Rosenblatt, who alleges that an agreement over a confidential 2025 deal was written on a signed napkin, according to court documents filed by Katherine Ratcliffe.
The Napkin Agreement and High Court Claim
The legal challenge centers on an oral agreement allegedly made in late 2022 over dinner at Simon Cowell’s London home. Katherine Ratcliffe, representing Ian Rosenblatt, stated in court filings that the terms of the offer were written on a napkin which Mr Cowell then signed. Mr Rosenblatt is seeking an agreed percentage of a confidential deal made in 2025, or alternatively £100,000 in damages for breach of contract.
According to the court documents, the napkin terms specified that Mr Rosenblatt would receive 8% of any deal over 30 million dollars, 10% of any deal over 50 million dollars, and 15% of any deal over 100 million dollars. Ms Ratcliffe said this arrangement was later written up and formally signed by Mr Cowell in February 2023 at his Cotswolds home.
Did you know?
Napkins and scraps of paper can occasionally hold legal weight in contract law if they contain the essential elements of a binding agreement—offer, acceptance, consideration, and the clear intention to create legal relations—alongside valid signatures.
Working Relationship and SyCo Entertainment Share Transfer
Mr Rosenblatt, who is a lawyer by profession, began working for Mr Cowell in 2018, according to Ms Ratcliffe’s submissions. During his tenure, Mr Rosenblatt helped facilitate the transfer of shares in SyCo Entertainment from Philip Green and Sony to the former X Factor judge. This left Mr Cowell with a 100% stake in the company from July 2020, after which Mr Rosenblatt was appointed director.
By late 2022, however, the working relationship had soured. Ms Ratcliffe noted in the documents that by September 2022, Mr Rosenblatt intended to formally resign and cease providing business advisory services “because of how challenging he had found working with Mr Cowell.” She added that it was “difficult to communicate” with Mr Cowell, describing him as “unpredictable” and “extremely emotional.”
Invoice Dispute Over the 2025 Deal
The dispute escalated after a major transaction was finalized in 2025. Mr Rosenblatt claims that when he submitted an invoice to Mr Cowell following the confidential deal, the agreed fee went unpaid. “In breach of the Dinner Agreement and/or the February 2023 Letter, the fee owed to Mr Rosenblatt has not been paid within 30 days of the date of the invoice or at all,” Ms Ratcliffe told the court.
As the legal proceedings move forward at the High Court in London, Mr Cowell has yet to file a defence to the claim. A spokesperson for Mr Cowell declined to comment when contacted regarding the litigation.
Pro Tip for Business Agreements
While informal or hastily drafted documents can sometimes form the basis of a contract in English law, commercial advisers strongly recommend formalizing all compensation structures and commission thresholds through structured legal channels to avoid costly litigation.
Frequently Asked Questions
Who is bringing the legal action against Simon Cowell?
Ian Rosenblatt, a lawyer and former business adviser to Mr Cowell, is bringing the challenge at the High Court in London through his representative, Katherine Ratcliffe.
What is the “napkin agreement”?
According to court documents, it is an informal agreement written on a napkin and signed by Mr Cowell over dinner at his London home in late 2022, outlining percentage payouts for future business deals.
What is Mr Rosenblatt seeking from the lawsuit?
He is seeking an agreed percentage of a confidential 2025 deal, or alternatively £100,000 in damages for breach of contract.
Has Mr Cowell responded to the claims?
Mr Cowell has not yet filed a formal defence in court, and a spokesperson for him declined to comment on the matter.
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