Linklaters' claim to this title is based on its involvement in about 100 green, social and sustainability bonds in 2019.

The venerable firm – founded in 1838 – claims to be at the forefront of developments in green and sustainable finance and has been involved in some of the biggest and most innovative transactions in the market. These include advising on the world's largest green bond and the first China green covered bonds.

The firm's green bond practice spans its European, North American and Asian offices and draws on support from its corporate, energy, financial regulation and environment and climate change teams.

Highlights of Linklaters' 2019 work in this area include:

•  Enel Finance International's €2.5 billion, ($2.7 billion) three-tranche bond linked to the UN's Sustainable Development Goals (SDGs). The coupon payments on this transaction will increase if Enel fails to meet certain targets linked to the SDGs. This was the first European bond whose payment terms were linked to sustainability goals. 
• Russian Railway's €500 million green bond, the first ever from Russia and the Commonwealth of Independent States.
• Link Real Estate Investment Trust's HKD4 billion ($510 million) issue of guaranteed green convertible bonds. This was the first green convertible bond globally in the real estate sector.
• The Government of Hong Kong's inaugural $1 billion transaction under its Government green bond programme, which was listed on both the London Stock Exchange and the Stock Exchange of Hong Kong.
• DTEK Renewables Finance's €325 million, five-year deal – the first ever green bond from a Ukrainian issuer.
• A £900 million ($1.2 billion) bond for wind energy giant Orsted, which was the biggest ever green bond denominated in sterling. Linklaters advised the banks involved in this transaction. 

The firm is bullish about the outlook for the market.

"2020 is set to be a bumper year for green bonds around the world as environmental impact becomes an even greater priority for investors and asset managers," said Richard O'Callaghan, capital markets partner.