Weil Gotshal & Manges' City office has bagged a first-time instruction for Japanese camera and medical devices company Olympus, advising opposite magic circle giant Allen & Overy (A&O) on the camera-maker's £1.03bn bid for Gyrus Group.

The referral came from the US law firm's New York office, where Olympus has been a client for several years, with the London arm winning the role following a presentation to the company.

The firm fielded a team led by London managing partner Mike Francies and corporate partner Ian Hamilton, with Akiko Mikumo -Olympus relationship partner and new Asian managing partner and Hong Kong office head for Weil Gotshal – taking the lead role on US issues.

The deal is the latest significant public M&A mandate for the firm's City arm in recent months, with the office also landing a role
acting for Boston-based publisher Houghton Mifflin on its $4bn (£1.96bn) acquisition of educational publishing operation Harcourt Education in July.

A&O advised long-term client, UK-based medical equipment maker Gyrus, on the takeover. A&O London corporate partner Ian Lopez led the firm's team, acting alongside competition partners Alistair Lindsay and Michael Jahnke.

The deal generated roles for several other law firms in both Tokyo and the UK, including Clifford Chance, which advised outside financer Sumitomo Mitsui Banking Corporation.

Meanwhile, Freshfields Bruckhaus Deringer advised Perella Weinberg Partners on its cash confirmation role, ensuring that the loan documentation – which was governed by Japanese law – met UK requirements. Freshfields corporate finance head Barry O'Brien led the firm's team, with advice in Tokyo given by corporate partner James Lawden.

Tokyo-based firm Mori Hamada & Matsumoto is understood to have advised Olympus on Japanese issues.

The deal, which is a relatively rare example of a Japanese corporate bidding for UK assets, is part of Olympus' bid to become a global leader in medical devices.

Lopez commented: "The acquisition is of strong strategic importance for both parties and presents key opportunities for Gyrus' stakeholders."

The deal is subject to approval from both the UK and US antitrust authorities, where both companies have a significant market share.