Allen & Overy (A&O) has hired two intellectual property (IP) partners from Simmons & Simmons in London, taking its haul from the UK firm to four in as many months.

The magic circle firm has hired IP partner Mark Heaney, who joined Simmons from US firm Baker Botts last year, alongside fellow Simmons IP partner David Stone (pictured).

Heaney was previously a partner in Bird & Bird's IP practice for 14 years, before joining Baker Botts in 2014. His practice focuses on patents, confidential information and copyright and related rights. Stone has been a partner at Simmons since 2008 and specialises in trademarks and registered/unregistered designs.

The pair are expected to join A&O in October.

News of the move comes a month after A&O hired Simmons' former London IP head Marc Doering, while in June the magic circle firm also took on Marjan Noor, who specialises in pharmaceutical patents, from Simmons. She is expected to join A&O this month.

The arrival of all four new partners will take A&O's London IP partner count to seven.

A&O London IP head Nicola Dagg said: "This is a real moment of transformational change for IP at A&O. Our corporate clients are increasingly becoming more tech focused and this has led to a massive demand for IP advice. We have a big pipeline of cutting-edge cases in London and we wanted more breadth and depth in the team to service those. These latest hires provide us with the sub-specialities we needed. Germany has to be the next chapter of our strategy for IP growth. We are also formulating plans for the US, where we currently don't have any IP litigators."

A&O London litigation head Karen Seward added: "One of the firm's strategic goals is to grow the litigation practice – we've made good progress over the past few years and this is another big step in the right direction."

The depatures, which will leave Simmons with 10 IP partners in London, come after the firm this week boosted its European ranks with the hire of Ashurst Brussels managing partner, Carl Meyntjens, as part of a corporate push in the Benelux region. Ashurst counsel Kelly Cherrette joined alongside him. The pair, who are both members of the Brussels bar, are expected to join Simmons' Brussels office on 1 December.