Directors of the public-private partnership behind the controversial Quaich Project have revealed they will "continue the history of recognising donors who make transformative donations to improve the gardens, citing the roles played by a gunmaker and a drinks giant in the 19th century.
They have admitted they may need to give corporate sponsors "brand profile or other recognition" in return for their backing for the £25 million venture.
However project leaders insist that the city council will have the "final say" on the locations of all corporate sponsorship in the gardens.
They were responding to criticism of secret brochures for a fundraising campaign to help pay for a radical overhaul of West Princes Street Gardens, which have been largely unchanged since they were opened to the public in the 1850s.
The Citizen campaign, which was set up last year to "defend" Edinburgh against the privatisation of public space, described the proposals as "devastating" and branded them "a debenture scheme by a private company the public has no control over."
The documents, which carry the city council's logo, reveal promises to big-money backers of access to high-profile celebrities, international publicity at VIP events as far afield as North America and Asia, tickets for high-profile concerts, exclusive drinks parties and dinners in a converted cottage in the gardens in return for their support.
Corporate backers will be able to link their brands to everything from new pathways and seating in the gardens to a 5000-capacity amphitheatre which will host up to 15 major events every year, as well as regular smaller-scale events.
Now it has emerged that the Quaich Project plans to replicate what happened in the 19th century when gunmaker Daniel Ross brought a French fountain at the Great Exhibition in London in 1962 and gifted it to Edinburgh.
A further act of generosity 15 years later by William Henry Ross, chair of the Distillers Company Limited, led to the first bandstand being built in the gardens.
If given the green light by councillors, the project would see a Hobbit House-style replacement for the existing Ross Bandstand, a two-storey visitor centre and hospitality complex overlooking Edinburgh Castle and a permanent cafe near the Ross Fountain.
Senior figures at the trust say the proposed replacement of the “outdated and inflexible” facilities at the existing bandstand, which dates back to 1935, would “open up possibilities” for the expanded use of the park throughout the year.
However less than £6 million has been raised so far for the project, which is believed to include a £5 million pledge from Norman Springford, who persuaded the council to join forces with him to pursue a joint redevelopment more than five years ago. The city council has pledged to contribute up to £5 million if there is a shortfall.
The Ross Development Trust, which Mr Springford set up to run an international design competition for an overhaul of the gardens, created the Quaich Project with the city council last year to raise the funding for the revamp and carry out the work in the gardens.
Potential backers are being told that for the project to be successful it needs “the active support and financial investment from a wide array of partners: businesses, philanthropists, charitable grant-making bodies and all those with a vested interest in improving this vital green space in the heart of Edinburgh.”
Jules Haston, director of development at the Quaich Project, said: "Edinburgh is a city built on philanthropy and it’s the far-sighted individuals and companies who we have to thank for many of the facilities that we enjoy today.
Edinburgh is a city built on philanthropy and it’s the far-sighted individuals and companies who we have to thank for many of the facilities that we enjoy today.
"We’re aiming to raise £25m to make our vision for West Princes Street Gardens a reality.
"We’ve got a long way to go but right now we’re working to raise awareness about the project and taking the plans step by step through the processes of planning and public consultations.
"The people that we are looking to for monetary support are individuals, charitable trusts and foundations, businesses and the public sector.
"Support from corporate partners is divided into corporate social responsibility i.e. donations through corporate membership – and corporate sponsorship.
"With the latter the supporting businesses may require some brand profile or other recognition. However, all corporate sponsorship located in the gardens will be subject to approval from the council.
"We will continue the history of recognising donors who make transformative donations to improve the gardens.
"This follows the tradition of the Ross Fountain and the Ross Bandstand where names which bear the names of two families (unrelated) who bestowed the gardens with generous gifts.
"This recognition may include naming rights of certain venues and facilities; this is a very common method of engaging and profiling supporters."
Terry Levinthal, director of the Cockburn Association heritage watchdog, said: "Brand profile or recognition is usually associated with a sponsorship arrangement and may therefore sit uneasily with the stated philanthropic ambitions set out.
The Ross Bandstand itself demonstrates that philanthropy can indeed be acknowledged through the naming of the actual gift where in this case the gift provided for the entire project. This is a world away from a mixed sponsorship/fund-raising approach.
The “Huawei Concert Pavilion” or the “Google Family Fun Zone” may not sit easily in West Princes Street Gardens, which is a public place and a Common Good Fund asset.
Whilst we are not suggesting that this is the approach being taken or is one that is even acceptable by the Ross Development Trust, the question has to be asked: 'If someone offers enough cash, then just how much brand recognition is for sale?' Once offered, it may be very difficult to refuse."
The leaked fundraising material, which has since been published on the Quaich Project website, states: “With unparalleled marketing potential in both location and profile, The Quaich Project offers a unique opportunity to sponsor a portfolio of brand new, world-class facilities.
“From new pathways and seating areas to adventure play parks and a 5000-capacity concert venue, there are various elements available to showcase your brand and increase experiential marketing activity.
"The Quaich Project will create new ways to celebrate Edinburgh’s status as one of the world’s most innovative, welcoming and thriving capitals - generating new global connections and raising this landmark location’s profile on the world stage.
"Our vision is to reimagine this place as a ‘space for all’ - bringing together the latest thinking in architectural, landscape and environmental design to create a joyful space that celebrates modernity and history, vibrancy and tranquility, practicality and artistry.
"Our sponsorship packages are tailored with your marketing, budget and business goals in mind.
"Each will be delivered by a dedicated account manager who will assist with monitoring and evaluation before, during and after the sponsorship’s activation."