None of the Cobbetts' partners joining DWF as part of last month's pre-pack deal will hold equity in DWF for at least 12 months, Legal Week can reveal.

Around 70 partners, including managing partner Nick Carr and senior partner Stephen Benson have made the move to DWF after the firm agreed to purchase Cobbetts' debts and work in progress (WIP) for a guaranteed £3.8m.

Speaking exclusively to Legal Week, DWF managing partner and chief executive Andrew Leaitherland (pictured) confirmed the decision, which will be revisited in 12 months' time. At the close of the last financial year DWF had 153 partners including 39 equity.

Leaitherland said: "We've been careful to protect our equity so any appointments are decided on a deal-by-deal basis. As a result of the Cobbetts deal, we've not expanded our equity base. The Cobbetts partners understand that it's difficult to be looking at equity straight away but we'll seek to realign them in a year's time once we have figured where their strengths lay."

Leaitherland also confirmed that neither Carr nor Benson will sit on DWF's executive or management team, with Carr set to take a lead on integration efforts before returning to full-time litigation practice, while Benson will not practice but will take a client-facing ambassadorial role.

The Cobbetts deal is DWF's fifth acquisition in just over a year (including a February tie-up with professional indemnity firm Fishburns), with the combinations meaning turnover will have moved from around £102m to more than £200m, while total headcount will top 2,500. It means the firm could be in line to enter the UK top 20 by revenue – two years ahead of schedule.

Leaitherland said: "Just look at what we've achieved in a year. We've managed to build a firm which now has revenues in excess of £200m and around 300 partners – we've doubled the size of the business. How have we financed it? Through good working capital. And although our debt will be up, we haven't doubled the level of debt and there's been no need for a capital call."

The pre-pack deal was finalised on 6 February, the day Cobbetts entered administration and one week after the firm had announced its intention to appoint administrators.

According to the Statement of Insolvency Practice (SIP) 16 document drawn up by administrators KPMG and seen by Legal Week, Cobbetts took the decision to seek a buyer for the business on 17 January when it became apparent that it couldn't meet financial requirements, including salary payments due around 20 February. According to the report, it was at this point when Cobbetts first contacted DWF with regards a sale.

"We were first contacted by Cobbetts in mid-January and everyone worked very hard in order to get an agreement finalised in 17 days," said Leaitherland. "For those who think this was a predetermined plan and that we had been in talks with Cobbetts all along, we hadn't. We were in the process of completing a merger with Fishburns so the timing of the Cobbetts talks proved to be somewhat of a logistical nightmare.

"Cobbetts couldn't have done much more. On both sides we tried to avoid insolvency and prevent administration but it had got to the point of no return. It was the unavoidable fixed costs that did for them – the die had been cast six years ago when they signed the terms of the Manchester office lease. To be fair, that was agreed during a buoyant market and they had planned to sub-let some of the floors but that didn't materialise."

According to the SIP report, DWF will also contribute £1.8m of the first £3.6m it realises from Cobbetts' debtors and WIP in order to cover the shortfall in the £8.3m owed by partners in professional practice loans – the bulk of which will come from the estimated £6.5m recouped in terminal loss relief.