Conservative donors who have collectively given the party more than £21m since 2001 have been declared as the ultimate owners of UK properties held through more than 150 offshore companies in a new government register. They include major property developers, such as the Reuben brothers, David and Simon, as well as Nick Candy, a UK-based businessman who owns a £160m flat and other properties through companies based in Guernsey. Others include Mohamed Amersi, the telecoms businessman who owns a London property through a British Virgin Islands (BVI) company, and Sanjeev Gupta, the metals tycoon behind the steel firm Liberty Global, who owns a Chelsea property through a company incorporated in the Bahamas. The register was created to increase transparency and help the tax authorities by showing the ultimate owners of British property held offshore. The Guardian believes there is a public interest in reporting on the business interests and property ownership structures of those who fund our major political parties, especially the party of government which makes laws around transparency. Holding properties through offshore companies is legal and some individuals may have genuine and legitimate privacy or security concerns or business reasons for using them. Some investors also cite the stability of the tax regime in jurisdictions such as Jersey and Guernsey for a reason their companies are based there, or they may live abroad. The tax regime has become less favourable for those holding property through offshore companies, which are liable for UK corporation tax, stamp duty, capital gains on property or share sales, and some are subject to an extra annual tax. However, the register shows thousands of investors choose to hold their property assets through offshore vehicles. All those named as beneficial owners on the register have complied with their legal obligations to declare their holdings. The property tycoons David and Simon Reuben are both listed as the beneficiaries of 106 companies that own property in the UK, mostly incorporated in the BVI. Among the UK properties is Admiralty Arch, held across three companies incorporated in Guernsey. The former government offices at the gateway to the Mall are being redeveloped into a luxury hotel and private residence. Through their firm Investors in Private Capital, the brothers have given more than £900,000 to the Conservative party since 2008. Investors in Private Capital also provided furnished office space for a year, worth £85,000, to Boris Johnson in September. A spokesperson for the Reuben brothers said: “All the entities are all liable to UK taxes and any taxes due have been paid in compliance with HMRC.” The telecoms businessman Mohamed Amersi is registered as the beneficial owner of a property in London through a BVI company. Amersi has given more than £400,000 to the Conservatives since 2018. Amersi told the Guardian the company was a development project he funded to convert the property into flats, most of which had been sold. He said the project had made a loss, and the company was “likely to be transferred to the long leaseholders of the flats for a nominal sum, allowing them to manage the property themselves”. He added: “My tax advisers have confirmed that the use of BVI companies has not had the effect of reducing my or anyone else’s tax liability in any way whatsoever.” Amersi also said the introduction of the register of overseas entities was a “positive development”. Gupta had no comment on his beneficial ownership of a west London property through a Bahamas company. He has given around £37,000 in auction gifts and hospitality to two Conservative MPs. The other donors on the list include two peers, Irvine Laidlaw, who donated around £3.2m when the Tories were in opposition, and Stanley Fink, a former Conservative party treasurer on a leave of absence from the Lords, who has given around £3.7m over 20 years. Fink owns part of the St Pancras Renaissance hotel building, in London, through a Guernsey-based vehicle. Fink said the structure had been set up before he was offered the opportunity to invest and he was passionate about the redevelopment of the Grade I-listed building. “I agreed to make the investment through the only vehicle offered to me. As I am UK resident, ordinarily resident and domiciled, I derive no benefit from this arrangement and indeed would have been equally happy or indeed happier with a UK structure,” Fink said. “To the best of my knowledge and belief I have gained no tax benefits from this structure whatsoever.” Laidlaw has a portfolio of offices and houses held through at least nine Isle of Man-based companies. Laidlaw, who retired from the Lords in 2010, did not respond to a request to comment through his foundation. Candy, who is resident and domiciled in the UK, owns a number of London properties through Guernsey-based vehicles. He has donated at least £270,000 to the Conservatives. His £160m flat in Knightsbridge, owned through a Guernsey company, is one of the most expensive in London and is currently for sale. It is understood the companies are all UK resident for corporation tax purposes, will pay UK tax on any gains and that the structure does not reduce any inheritance or other tax liability. Amjad Bseisu, the chief executive of the oil firm EnQuest, who has given more than £450,000 to the Conservatives over the last 10 years, owns a flat in central London through a BVI company. Bseisu said: “I confirm that I am the ultimate beneficial owner of Solway Enterprises Ltd [a BVI company], having acquired a controlling interest. SEL pays the same UK corporation tax on its rental profits and any future capital gains as any UK company. There is no present or future UK tax advantage that either myself or SEL enjoys by SEL being a non-UK company. I can confirm that during my period of beneficial ownership SEL has been compliant with all UK tax reporting.” India’s former solicitor general Harish Salve owns a flat in Mayfair through a company incorporated in the BVI. Salve said the overseas ownership structure was established prior to his purchase of the property by its previous owner, and that inheritance tax would be paid on it. Salve donated £23,000 to the Conservatives in 2022. “As a tax lawyer, I wholeheartedly welcome the government’s move to have a register of overseas properties,” Salve said. “It is not just in the interest of the exchequer but also in the interests of transparency that the ownership of properties be disclosed and the name of the ultimate beneficial owner be in public domain.” One former donor, the venture capitalist Jon Moulton, who gave more than £300,000 between 2004 and 2011, holds a property in central London through companies based in Guernsey. Moulton said he held them in Guernsey because he lives there, and described the register as “just more paperwork for me”. He said it did not reduce his tax liability and added: “I think I’m actually potentially worse off than UK resident owners on some taxes.”