Two more proxy advisory firms have recommended PartnerRe shareholders to vote against a merger with Axis Capital.

Proxy Mosaic said that a rival all-cash $6.8 billion bid by Italian investment firm Exor for PartnerRe “outweighs the potential upside in the Axis’ economically inferior offer.”

It added: “We suspect that the upside to the merger has been exaggerated with multiple expansion proving optimistic and the synergy realisation timeline too aggressive.”

The Proxy Mosaic report said: “It is also worth noting that this Axis premium may be somewhat ‘illusory’ in the sense that Axis stock price seems to be buoyed by external factors, such as the possibility that Axis itself may be a target of Arch Capital if this particular deal falls through, as well as the fact that Axis would be due a $280-million termination fee if Exor is successful in acquiring PartnerRe.”

Egan-Jones, a major US proxy advisory firm, on Thursday also recommended that PartnerRe shareholders reject the Axis merger.

But it added that it had advised for the merger on the Axis proxy “since the merger as structured would represent very favourable terms for that company’s shareholders — indeed terms that appear to be too good and hence one-sided in our opinion.”

Institutional Shareholders Services and Glass Lewis & Co have also recommended PartnerRe shareholders ditch the proposed deal with Axis.

Shareholders in both firms — near-neighbours on Pitts Bay Road — will vote on the merger proposal on Friday.