Former Quinn Emanuel Urquhart & Sullivan London partner Mark Hastings – who was dismissed by the firm earlier this year after being accused of inappropriate behaviour – has resurfaced at a Mayfair boutique amid a Solicitors Regulation Authority (SRA) investigation into the allegations.

Hastings, who is currently being investigated by the SRA over claims made by two members of staff at Quinn, joined disputes boutique Grosvenor Law as a partner last month.

Grosvenor, which describes itself as a "specialist personal and business dispute resolution firm", focuses on advising corporate clients and high-net-worth individuals. According to its website, it has four other partners, including founder Dan Morrison, the former head of banking and finance at Mishcon de Reya.

Hastings spent 18 months at Quinn Emanuel after joining the US firm in December 2016 from Addleshaw Goddard. He was asked to leave with immediate effect this May following an investigation into his behaviour prompted by allegations made against him by two members of staff.

He was suspended while the firm commissioned an investigation led by Mishcon partner and business crime head Alison Levitt QC, whose findings were presented to Quinn in late April. Hastings was subsequently dismissed without compensation and the US firm referred itself to the SRA as a result of the episode.

A spokesperson at the SRA – which is still considering whether to launch an investigation into Quinn Emanuel's handling of the issue – confirmed it is investigating Hastings, adding: "We are investigating before deciding on appropriate action."

In a statement, Grosvenor partner Daniel Astaire said: "Mark is an excellent practitioner and his appointment bolsters our growing team. No comment will be made into alleged matters with another firm."

Prior to his move to Quinn, Hastings was head of civil fraud at Addleshaws, where he was a partner for seven years. He was one of the firm's most high-profile lawyers, acting for oligarch Boris Berezovsky on a series of major cases, including a $6bn commercial court dispute with Chelsea Football Club owner Roman Abramovich.

A number of partners have been ousted by law firms this year after allegations of inappropriate behaviour, including former Latham & Watkins chair Bill Voge, who admitted to "communications of a sexual nature" with a woman he met through a Christian support group; and a Baker McKenzie partner who left the firm after allegedly assaulting a female associate several years ago.