Contact details

Mario  Betts

T: +44 20 7809 2151 M:+44 7787 060 100 Email Mario | vCard Office: London

Mario Betts Managing associate

Contact details

Mario  Betts

Mario Betts
Managing associate

T: +44 20 7809 2151 M: +44 7787 060 100 Email Mario | vCard Office: London

Mario Betts is a managing associate in the commercial litigation department specialising in commercial property disputes. Mario is described variously in the Legal Directories as "a first-rate property litigation solicitor" with "excellent commercial awareness" and "a complete delight to work with".
  • Profile
  • Services

Mario advises on a range of contentious property issues including commercial lease renewals, dilapidations, rent review, service charge disputes, forfeiture proceedings, break notices and has a particular specialism in insolvency related property disputes including advising on disclaimed leases, CVAs, administrations and liquidations. 

Mario also advises on property related professional negligence (particularly involving solicitors and surveyors) and development issues such as boundary disputes, easements and the enforceability of restrictive covenants. 

Mario is a member of the Property Litigation Association, R3 – the Association of Business Recovery professionals, NARA (Association of Property and Fixed Charge Receivers) and the Insolvency Practitioners Association.

'Mario Betts is a top litigator. He is decisive, bright and very driven.' 
The Legal 500 2024

  • Real estate litigation
  • Commercial litigation

Lease renewals

Mario regularly advises both landlords and tenants on all aspects of contested/uncontested 1954 Act lease renewals including recently successfully opposing a landlord’s ‘ground (g)’ claim following a 3 day trial and successfully opposing the landlord’s appeal in the High Court in what is now one of the leading cases on 'ground (g)'.  


Mario has acted – on both sides – on a number of high value and disputed forfeiture claims.  Recent examples include forfeiting the lease of a high-end art gallery in Mayfair where the outstanding rent exceeded £1.5 million and forfeiting the lease of office premises in Mayfair where the tenant company and its beneficial owner were both subject the UK 'Russia Sanctions' which raised complex and unprecedented issues concerning what steps could be in relation expensive artwork and paintings which remained on the premises. 


Advising a major national restaurant chain on the property aspects of its CVA proposal and associated litigation relating to the effect of forfeiture and waiver in the context of a CVA.

Advising a bank in relation to the default by its mortgagor and subsequent possession proceedings in respect of a £20 million country estate, including the appointment of an LPA Receiver and subsequent disputed sale of the estate.

Advising a commercial tenant following the disclaimer of its landlord’s headlease arising out of the Carillion Group liquidation


Acting in the High Court for the owner on of two adjoining townhouses on Park Lane on the disputed acquisition of its properties under the Leasehold Reform Act 1967.

Advising an owner of a large block of flats on Park Lane in relation to a substantial claim brought a long leaseholder of the penthouse flat who was also a property developer. The claim comprised various elements including a valuable claim by the leaseholder for proprietary estoppel to extend his flat into the airspace.

More: Real estate litigation

Contract disputes

Successfully advising on a multi-million pound claim relating to the termination of a contract for sale of a landmark London property including claims for misrepresentation, waiver and estoppel.

Advising a landlord client in relation to a substantial contractual dispute with its tenant arising out of the interpretation of a clause in an agreement for lease requiring the client to contribute £5m to the tenant's fit out costs. 

Professional negligence

Successfully advising on professional negligence claims against a top 50 firm of solicitors and a firm of surveyors relating to a misstate in a property transaction.


Advising a property owner and successfully obtaining an injunction against its mortgagee and various related third parties restraining them from disposing of the mortgaged property following a sale at an undervalue.

More: Commercial litigation

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