The German utility giant has turned to Financial Dynamics to handle all communications surrounding the deal, which is expected to close in July.
RWE, which is based in Essen, continues to retain Hill & Knowlton for general financial, corporate and sponsorship PR, but brought in the FD team to work on the bid, announced last Friday.
FD - which worked for RWE before when it was drafted in for its takeover of Thames Water 18 months ago - is working to communicate the benefits of the deal to the media and investors.
'The key message is synergies and RWE's vision of providing a range of utilities under one brand,' said FD chief executive Charles Watson.
The FD team is led by director Andrew Dowler, who reports to RWE corporate comms manager Bill McAndrews.
'The job is two-fold. First, to persuade Innogy's shareholders that the offer RWE made is fair and reasonable. Second, to help RWE explain to its shareholders through the analyst community and the press that it would benefit from buying Innogy,' said Dowler.
Though the deal is friendly, Dowler said one of the main challenges is getting the messages across to Innogy's retail shareholders, which are ten per cent of the total.
'With retail investors, it's a matter of keeping the issue alive in the press so that they know the documents they have received should be read and acted upon,' said Dowler.
Meanwhile, FD this week welcomed its former chairman Tony Knox back as a non-executive chairman nearly 18 months after he retired.
He will devote around two days a week to his role with the agency, which he co-founded in 1986.
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