Monckton Chambers and 4-5 Gray's Inn Square have entered merger talks.
The news comes a week after it was revealed that seven tenants are leaving 4-5 Gray's Inn, including Cherie Booth QC and David Bean QC, for the new 22-tenant human rights set Matrix Chambers, which is also taking Jessica Simor and Rhodri Thompson from Monckton Chambers.
Chambers director at 4-5 Gray's Inn Tony Wells says: "There were informal soundings taking place before Cherie Booth's announcement. We are now seriously examining the feasibility of merging."
Alexandrina le Clezio, Monckton's chambers director, says: "We are commencing talks with 4-5 Gray's Inn Square with a view to implementing a full merger.
"Discussions between members of chambers are taking place and we expect to make an announcement in three weeks."
Legal commentators say a fused set makes strong business sense and would represent a formidable chambers with 75 tenants, including 25 silks.
There is a strong synergy between 4-5 Gray's Inn's strengths in public, planning and commercial law with Monckton's public, European and competition law focus.
Monckton recently poached former attorney-general Sir Nicholas Lyell QC from magic circle set Brick Court (The Lawyer, 10 January).
The commercial big-hitters and planning silks have all remained at 4-5 Gray's Inn and it is not expected that the loss of Booth and the others will make any significant financial dent to the set's earning power.
Michael Beloff QC, who is stepping down as head of 4-5 Gray's Inn to concentrate on his responsibilities as president of Trinity College, Oxford, has been invited to join Matrix. He will make a decision by Easter.
But whether he stays put, goes to Matrix or joins another set, Beloff stresses that he will not head any chambers because of the demands of university work.