The costs of acquiring Nabarro and Olswang have been laid bare in CMS's 2017-18 limited liability partnership accounts, offering the first detailed insight into the financial implications of the three-way merger.

The accounts – which cover the global firm's UK arm, now known as CMS Cameron McKenna Nabarro Olswang – reveal that on the 1 May 2017 transaction date, Nabarro had net assets of £51.3m, and Olswang £15.5m, equating to a total acquisition cost of £66.8m.

The acquisition costs include assets and cash in the bank, minus the figures the two firms owed to creditors, which stood at £37.7m for Nabarro and £42m for Olswang.

The accounts also reveal that shortly after the merger in September 2017, CMS set up an £85m unsecured revolving credit facility with Lloyds Bank and RBS, which the firm said was to cover "the short-term financing of merger costs and fit-out of premises, as well as providing a contingency fund, should it be needed". Last July, the facility was stepped down early to £65m.

The filing also showed a total of £28.9m has been charged to the group profit and loss account in respect of "costs incurred in reorganising, restructuring and integrating" the three firms in the wake of the merger. Last year, CMS managing partner Stephen Millar told Legal Week that the cost of combining the three firms would be about £45m, paid over two years.

The three-way combination created a firm with revenues of £521.9m, up 88% from CMS Cameron McKenna's 2016-17 revenues of £277.5m, according to the accounts. On a like-for-like basis, the £521.9m figure is approximately 3.5% up on the combined 2016-17 revenues for CMS, Nabarro (£131.1m) and Olswang (£95.8m).

The best-paid partner at the combined firm took home £1m during 2017-18, up from CMS Cameron McKenna's equivalent pre-merger figure of £798,000. Nabarro's top-of-equity figure for the final year before the merger stood at £1.07m, while Olswang's best-paid partner took home £727,000 in 2016-17.

The accounts explain that CMS intends to eliminate legacy Nabarro's pensions deficit, estimating that £4.85m in contributions will be paid into the scheme this year as part of a push to pay off the deficit in its entirety by 1 May 2022.

CMS, Olswang and Nabarro merged on 1 May 2017, creating the eighth-largest firm in the UK. The average number of partners at the combined firm is 376, which is 178 up from CMS Cameron McKenna's pre-merger figure of 198.

With the addition of Olswang and Nabarro, total staff headcount rose 43% to 2,370, with salary costs more than doubling from £74.1m to £163m. 

Total remuneration for the firm's key management personnel increased from £2.8m to £3.9m, although the firm declined to specify which partners are included in this group and how it had changed in the wake of the merger.

Last June, CMS posted global revenues of €1.3bn (£1.15bn) for the 2017 calendar year, in its first combined results since the merger.