The London Stock Exchange (LSE) and Deutsche Boerse have yet to decide whether shareholders will be asked to vote on their proposed merger before the EU referendum.
City A.M. understands shareholders will be presented with a prospectus containing details of when the merger will be voted on before 23 June.
But the stock exchanges are undecided on whether shareholders will be asked to vote on the proposed deal before the referendum.
On publishing the deal prospectus, a date will be set for an LSE extraordinary general meeting (EGM), which should take place a minimum of three weeks later. The German shareholder process is understood to be a lengthier one.
Intercontinental Exchange (ICE), the owner of the New York Stock Exchange, is currently considering whether to make a takeover bid for the LSE.
It would need to do so at least seven days before the shareholder vote.
And analysts believe the US company will wait as long as possible before making its move.
An investor note from Exane BNP Paribas last week suggested ICE will wait for as long as possible before making a formal approach because "Brexit carries downside risk on the value of LSE".
The note, by Arnaud Giblat and Gregory Simpson, also suggested there is a “good probability of LSE remaining a standalone company”, meaning no deal with Deutsche Boerse or ICE.
Giblat and Simpson also expressed confusion over “numerous hostile comments about a potential bid from ICE” made by LSE chief executive Xavier Rolet.
The note said: “It is unclear to us why management would be so hostile, when ICE may table an economically superior bid to that of [Deutsche Boerse].
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“In any case, this reduces the chances of a friendly deal as well as the probability of a bid being forthcoming.
“We continue to see a high likelihood of a bid given this ‘rare’ availability of a strategic asset.
LSE and Deutsche Boerse declined to comment.